On the other hand, quite a few online backup services automatically store all your data safely off-site. The included software typically offers two key features to minimize bandwidth usage and storage space, while increasing speed. First, they usually back up only the portions of files that have changed since the previous backup run, not the entire files. And second, they generally support deduplication, which avoids copying the same data more than once. Products in this category include Backblaze ($5 per month), EMC's MozyHome ($5 per month), and CrashPlan Central ($54 per year for a single computer; $100 per year for a family plan). All these let you back up unlimited data online for a flat fee. But CrashPlan stands out as the only provider that also lets you back up to a local disk or a disk shared by a friend--anywhere in the world--rather than (or in addition to) paying for the company's own online storage. You can do this with the free CrashPlan software or the $60 CrashPlan+, which also backs up your files continuously, as they change, and lets you restore files from CrashPlan Central through any Web browser.
No encryption Time Machine doesn't natively offer encrypted backups (although see this hint for one way around that problem), and to add insult to injury, it makes a poor match for OS X's FileVault encryption. With FileVault enabled, Time Machine can back up your files only when you're logged out, and if you want to restore a backed-up file, you must do so manually--the 3D star field interface won't work.
All the providers of online backup services mentioned just above also encrypt your backups automatically. Other, more-conventional backup software that also offers encryption includes Prosoft Engineering's Data Backup ($59), Intego's Personal Backup (a component of Internet Security Barrier, $80), and Tri-Edre's Tri-Backup ($69). All of these also let you create bootable duplicates and versioned backups.