In "Online Backup Options Expand" (2007-04-09), I mentioned two potentially promising online backup services - Mozy and Bandwagon - that were not quite ready for prime time. Last week, both services announced that they are officially available for public beta testing.
Berkeley Data Systems' Mozy offers unlimited online storage for a mere $5 per month. Their Mac backup client, previously in a limited beta, is now available for anyone to download. If you're not ready to spring for the monthly fee or have only a few files to back up, you can sign up for 2 GB of storage at no cost. Although the current version of Mozy is a bit better than the one I looked at a few weeks ago, it's still clearly a beta. Among the problems yet to be ironed out are aggravating delays (over an hour on my test machine) in opening the configuration window - every time you open it! - and occasional hangs during backup or when attempting to cancel a backup in progress. The Mozy download weighs in at 5 MB.
Bandwagon DIY from Xackup uses storage space you've set up separately on Amazon.com's S3 service to back up your iTunes content online. When the beta program ends sometime in May, prices (not counting storage space) will be $2 per month for the standard Bandwagon DIY service and $3 per month for Bandwagon DIY+, which also supports syncing iTunes content between two Macs. Bandwagon DIY beta 1 is a 4 MB download.