CrashPlan+

Reviewers are mightily impressed with CrashPlan+, an online backup service that also backs up your files to an external hard drive and/or another computer. You can even save your files to a friend's computer (or any other Internet-connected computer) as long as he or she has a CrashPlan account.

If you don't need to back up your files to CrashPlan's servers, local backup and backing up to another computer are available for free as part of the basic CrashPlan client. However, reviewers say that the subscription-based CrashPlan+ is a great value, giving you unlimited storage for a single PC for just $50 a year -- less than any other online backup service that provides unlimited storage. In fact, between the cheap online storage and robust local and network backup options available with CrashPlan+, reviewers say the service offers the best value, dollar for dollar.

Experts also say that the ability to back up your files to three separate locations provides better security than relying solely on an online provider. Unlimited file versioning is a boon if you ever want to restore a previous revision of a file that you've long since written over, and CrashPlan+ protects your data with 448-bit Blowfish encryption. Users of the free CrashPlan service only get 128-bit encryption, however.

The interface is easy to use, reviews say. It's also easy to manually select your files if you don't want to back up automatically. Like its competitors, CrashPlan+ only backs up files when they've been altered but, unlike the others, CrashPlan stores files forever -- it never deletes your data, enabling you to recover long-deleted files easily.

However, reviewers say CrashPlan+ makes it a little complicated to limit the bandwidth if you're doing something else on your computer, and testers report that the data transfer between your PC and CrashPlan's servers is very slow. Others dislike that there is no visual indication of whether a file is backed up or waiting to be backed up. Reviewers also remark disparagingly on the ads found in the free version of CrashPlan, though those are eliminated with premium subscriptions.

Other than the three-pronged backup options, CrashPlan+ offers little in the way of additional features, though support for the Linux operating system is a notable plus for some. Few online backup services offer Linux support, including well-rated options such as MozyHome (*Est. $6 per month for 50 GB) or SOS Online Backup (*Est. $80 per year for 50 GB).

The best reviews of CrashPlan and CrashPlan+ come from MacFormat (based in the U.K.), Macworld and Computerworld.com, each of which tests and compares multiple online backup services. Each service is rated and editors declare a winner. About.com and Maximum PC magazine also offer comparative roundups, though those aren't as in-depth. PCMag.com and Lifehacker.com also have single-product reviews that compares CrashPlan to other options.