For some people, opting for Jungle Disk's well-financed Rackspace or S3 servers offers extra peace of mind.

Price is always an issue, coupled with ease of use. CrashPlan gets the highest marks for interface design, simplicity, options, and cost for two or more computers. CrashPlan also adds desktop and personal remote backup (to other computers you own or to those of your friends) in the same software at no extra cost. (An upgrade to CrashPlan+ adds a handful of features for desktop backup.)

For those who want to mount a backup drive locally, and who want more precise control over every tiny aspect of backups--and who have relatively small backup sets--Jungle Disk provides odd software but all the options you could ever need. For 50GB of stored backups, the cost is $7.50 in storage; for truly large backup sets, an unlimited option is the only choice.