There are networked hard drives from several manufacturers that can back up both laptops wirelessly and allow sharing. One I reviewed recently is the My Book World Edition from Western Digital. Another approach would be to use a Web-based synchronization service. My favorite of these is called SugarSync, from a company called Sharpcast.

SugarSync can automatically, and almost instantly, synchronize files in folders you select among multiple computers, while also backing them up to a password-protected Web account. SugarSync starts at $5 a month or $50 a year for 30 gigabytes of files, and goes up in price based on the amount you use. The company offers a free two-gigabyte account and a free trial of larger accounts for 30 days. More information is at sharpcast.com.

I have been a Windows user for may years but have wanted to change to Mac. Yet every article I read says that Quicken, which I depend upon heavily, will not run—at least reliably—on a Mac, even with the Windows-compatible software. Is this true?

The native Quicken version for the Mac is a less capable program than the Windows version, and doesn’t use the same file format, which makes importing Windows Quicken files a tedious and imperfect process for many users. Intuit, the maker of Quicken, is promising a new, much better native Mac version early next year that it claims will solve these problems, but I haven’t tested it, so I can’t verify that pledge.

However, in tests I have run periodically, Quicken for Windows ran just fine on a Mac equipped to run Windows and Windows programs. This was true when I used either Parallels or Fusion, which allow you to run Windows programs on a Mac simultaneously with Mac programs; or when I used Boot Camp, which converts the Mac into a full-fledged Windows machine, with Apple’s operating system turned off.

I plan to get a new computer after Windows 7 is released in October, to replace my old Compaq running Windows XP. Will I have difficulty moving my files to the new one?

You shouldn’t have much difficulty with your personal data files. Microsoft is building in an Easy Transfer program to move personal files to a new Windows 7 PC. But the Microsoft program won’t move over your programs. You will have to reinstall all your programs, which means finding your installation disks or installer files and re-installing all the updates from that have occurred over the years. A company called LapLink is promising to sell software it says will automate the entire process, including moving programs, to spare you this re-installation burden. But it isn’t out yet, and I haven’t tested it with Windows 7.

You can find Mossberg’s Mailbox and my other columns at the All Things Digital Web site, http://walt.allthingsd.com.

Has anyone come up with a method that allows people to take pictures with a regular digital camera and then download them wirelessly to a computer, and/or perhaps to the Internet?

There have been a few digital cameras with built-in Wi-Fi wireless capability, but the best and simplest method I know is a $100 product called Eye-Fi. This tiny gadget looks and works like a regular, garden-variety SD memory card, but it packs a Wi-Fi transmitter inside. It fits into a standard SD memory-card slot and is compatible with a wide range of camera models from Canon (CAJ), Kodak (EK), Nikon (NINOF.PK) and others.

Coupled with clever software, and a clever Web site, the Eye-Fi card automatically zips your pictures wirelessly to your PC or Mac, and/or to your choice of over 20 online photo-sharing services.

For more information, see www.eye.fi. For a list of compatible cameras, see support.eye.fi/compatibility/. For a full review of the product, see: solution.allthingsd.com/20071121/.

You mentioned last week that SugarSync might be a good solution for backups, so if one computer dies your files still exist on another system. But what if the doomed computer doesn’t actually die but its files are corrupted by malicious software? Do those newly corrupted files overwrite the good copies on your SugarSync network?

They could do so, depending on which folders you had chosen to replicate on your other computers. Automatic-synchronization services like SugarSync have a tough time telling whether changes to a file are deliberate, accidental or the result of some sort of corruption. Though the last is rare, it could look to SugarSync like you had changed the file on purpose.

One way to guard against that is for a service to offer “versioning” — the practice of maintaining multiple past copies of a file. That way, if a change isn’t intentional, you can go back to the prior, pristine version. Sharpcast, the company that makes SugarSync, says it is planning to add versioning to the service, but offers no specific date. In the meantime, one way to back up a file without fear of its being overwritten by a corrupted version is to upload it to SugarSync’s special “Web Archive” folder, whose contents are never automatically updated.

Have you ever reviewed and suggested a media player for connecting to a home theater to play all songs, videos and photos that exist on your home computers?

Yes, I have reviewed several over the years. The one I find simplest and best designed is Apple TV, which, despite its name, can work fine in a household with no other Apple (AAPL) hardware. It costs $229 and is a small, thin, unobtrusive box that fetches music, photos and videos from your home network using either a wired or a wireless connection. It can connect to your TV set or home theater via a variety of analog and digital ports, including component-video, HDMI, and optical and analog audio. It supports high-definition video and works with any computer, Windows or Mac, that has Apple’s free iTunes software installed and running.

Apple TV handles many standard photo, music and video formats, but it is limited to music and video files that iTunes can handle. That excludes copy-protected files in Microsoft’s formats, and certain open Microsoft formats, but includes common files like MP3s. Apple TV also allows you to access YouTube and to purchase music and TV shows from Apple, and rent movies from Apple, without the use of a computer.

• You can find Mossberg’s Mailbox, and my other columns, online for free at the new All Things Digital Web site, http://walt.allthingsd.com.

Tubes installs a program on the desktop (right) into which files can be dragged and shared using automatic synchronization.

This week, I tested another product in the long line of programs that uses automatic synchronization to simplify the process of sharing large files by giving you the ability to change files and privacy options at any time. It’s called Tubes (www.tubesnow.com) from Tubes Networks and it takes its name from the pneumatic vacuum-tube system commonly used in bank drive-throughs that motivated me to join my Mom on visits to the bank as a kid. Mom would pull up and a container would whoosh over through a tube to arrive beside the car window; after a quick exchange it returned with her deposit slip and a lollipop for me.

Tubes aims to work with the same sort of magic. Once installed, its desktop application stays opened on your computer as a place where “tubes” are made for sending files. Any type of file can be dragged, dropped and sent off to share with other people using these virtual tubes. As soon as you release data into a tube, a whoosh sounds (like that of the vacuum tube) and your files are encrypted and uploaded to the Tubes server.

Invited guests view your tube’s data in its full, uncompressed format. The owner of the tube always has the final say on what is shared with whom, and changes made to tubes on your hard drive are detected instantly via automatic synchronization, guaranteeing viewers will always see the latest version of the tube. Shared tubes are also accessible via the Web, saving viewers from downloading the Tubes desktop program.

Other products like Sharpcast (www.sharpcast.com) and Pando (www.pando.com) also offer ways to share large digital files; Sharpcast uses synchronization similar to that of Tubes — it all happens behind the scenes without any work on the user’s part.

Tubes is available in a free version that provides a gigabyte of storage, or in paid versions with five, 10 and 20 gigabytes of storage for $6, $11 or $21, respectively.

Most of the time, Tubes worked well for me when I installed it on two Windows machines, one running XP and one running Vista. Tubes’ smart use of an already familiar process — dragging and dropping — gives you the impression that you already know how to use it and makes sharing files seem easy. I started dragging all sorts of files into tubes that I created, naming them and labeling them with a representative icon (one of 10 offered by Tubes or one of my own images).

For all its usefulness, Tubes certainly has room for improvement. For now, there isn’t a Mac version of the program, and when friends and I tried accessing shared tubes using a Mac Web browser, the results were inconsistent and sometimes didn’t work at all. Windows Vista had its own issues. After installing Tubes on my Vista laptop, an error message labeled “invalid argument” made me feel like a member of the debate team. And I couldn’t see thumbnail images of photos in my tubes using Vista, though I could on Windows XP.

Today, Tubes is releasing an updated version of its program that aims to improve the usability and look of the product, including refining the processes of sharing tubes and looking at tubes via the Web.

Before sharing tubes, I adjusted the permissions granted to each guest by labeling them as a Reader, Author or Editor; only the Owner can invite others to view a tube. But these labels can get confusing. More than once, I granted guests the highest level of permission, which is Editor, allowing them to make changes to the files in my tube, only for the guest to be asked for his registered Tubes email and password, which an invited guest shouldn’t need.

The Tubes experience was best when the recipient of my Tubes invitations had the application installed on his or her desktop.

After installing Tubes on a computer at work, I installed it on my home PC and easily auto-synched tubes that I created at work onto my home PC — a big plus.

Tubes incorporates the Web by assigning a unique URL to every file in every tube, and every tube automatically generates its own Web site, or “tubeSite,” as it’s called. Individual URLs for each file can be found by right clicking on a file and selecting an option to copy the URL into an email or browser. I copied the URL of a shared MP3 audio file and pasted it into my browser; it played a Fountains of Wayne song with no problem. But sharing these URLs with others is only possible if the owner gives permission.

Comments about tubes can be made in the “tubeBlog” — accessible through any tube in the application or online. I created a tubeBlog for a tube with photos from one of my vacations, adding descriptions and comments to specific photos. Others, with my permission, could do the same, using the photos from the tube or just leaving comments.

A friend used Tubes to share photos with me while vacationing in Italy and Amsterdam. I added my own travel photos and an itinerary made in Microsoft Word to his tube and changed the tube’s title; these alterations synched instantly.

Even if you aren’t online, you can access tubes or make changes to them by dragging files in or taking them out; updates are made automatically the next time your computer connects to the Web.

Tubes is off to a good start, but it needs to improve its system to make permission levels more understandable for tube owners and those invited to see a shared tube. With a few improvements, Tubes could be a product that I’ll continue using on Windows computers long after this column.

Email mossbergsolution@wsj.com

Write to Katherine Boehret at katie.boehret@wsj.com

Inside big corporations, these tasks often are handled by internal networks, which store files centrally and back up computers nightly. But consumers have had to resort to time-consuming and imperfect methods. These include emailing files to themselves, manually synchronizing their phones and computers, and manually copying files among their computers.

Over the next year or so, I expect that one of the big trends in personal technology will be the introduction of services and products that make this job easier.

Both Google and Microsoft are reportedly preparing new services that will back up all of a consumer’s data to their servers. Apple already offers a service called .Mac, which, for $99 a year, gives consumers storage space on an Apple server, allows backups to that remote server and synchronizes selected data among multiple Macs. And Microsoft has recently acquired a small service called FolderShare, which I reviewed last year, that can synchronize and back up selected folders on any mix of Windows and Macintosh computers.

Now, a small Silicon Valley start-up called Sharpcast is introducing an impressive, free service that synchronizes data among PCs, phones and a Web site at lightning speeds. I tested Sharpcast for several weeks, and found that it works really well. You can try it out at www.sharpcast.com.

In this first incarnation — a beta, or test, version — Sharpcast works only with photos. But it plans this year to add synchronization of contacts and calendar entries and, eventually, other types of data. If the service can handle these other data types as well as it handles photos, Sharpcast will be a real boon to consumers.

With Sharpcast Photos, any change you make to an album of photos on one of your devices is replicated within seconds on your other devices. If you add a photo to an album on your PC, it shows up within seconds on your phone and on your Sharpcast Web page. If you rotate a photo on the phone, the same photo is rotated within seconds on the PC and Web page. If you delete a photo on the Web page, it’s immediately deleted on the PC and the phone. And if you take a photo with the camera on your Sharpcast-enabled phone, it will show up in seconds on your PC and your Web page.

You can also share your albums with other Sharpcast users, and receive shared albums from them. By synchronizing your photos among multiple devices and a Web site, Sharpcast is also backing them up, so the loss of one device won’t mean the loss of your prized pictures.

In its first version, Sharpcast works only with photos.

On your PC or phone, Sharpcast works through a software program you download from the company’s Web site. You can also access the service, and your photos, from a personal Web page Sharpcast provides, without using any Sharpcast software.

For now, the Sharpcast Photos software works only on PCs running Windows XP, and on a few high-end phones, like the Palm Treo 700w and the Motorola Q, that run Windows Mobile 5.0 software. The company plans to support more phones soon. It is also working on a Macintosh version. Today, Mac owners can use Sharpcast via the Web page, which isn’t quite as capable or fast as the Windows software, but still works well.

Sharpcast’s phone software is in an even earlier stage than the PC software or the Web site, and lacks all of their capabilities, especially the ability to share albums and view albums shared with you by others. But it works.

I tested Sharpcast using three devices — a Windows PC and a Palm Treo 700w running Sharpcast’s software, and a Macintosh computer logged into my personal page at the Sharpcast Web site.

Using the Windows software on a PC, and the Web site via my Mac, I easily created 10 albums. I added and deleted photos, rotated them, and created and edited captions on all three devices. In every case, Sharpcast faithfully and rapidly replicated my changes on the other devices.

In this first version of Sharpcast, you can’t edit photos or comment on shared photo albums or print pictures. The company says it will be adding some of these features next month and others in the fall. Also, Sharpcast currently compresses your photos before storing them, but future versions will store pictures at full resolution. As it gains more capability, Sharpcast plans to continue offering a free service, but will also add paid tiers of service.

Sharpcast also plans to extend its synchronization technology to other kinds of data besides photos. At The Wall Street Journal’s annual D: All Things Digital conference last month, the company demonstrated a future product that will synchronize contacts.

Sharpcast is a very cool and compelling service that solves a real problem. And it promises to get even better.

• Email me at mossberg@wsj.com.