I really recommend @crashplan (http://www.crashplan.com). After using Mozy for almost 2 years, I decided to move when they removed their "unlimited" plan. I store over 500GB of data between 4 machines: Mac, PC &amp; Linux. Really reliable and as soon as the file is completed sending it is able to be restored, I haven't seen this feature with other services. Most require a "full-backup" to be complete for any restore. They also offer local and pc-to-pc backups for free.