Awesome. We're about half way through moving from our janky Exchange 2003 servers to our Exchange 2007 Ultra Clusters... and the Exchange 2003 server decides to take a digger last night. Not just a digger (lost three! less then a year old SCSI3 disks in a 0+1 array in a matter of 2 days), but we don't have current backups... Using Active@Undelete to try and recover some data. It's a blast and a half. At least we've got affect people backup with a dial-tone mailbox on our hot spare 2003 box.
Moral of the story: nightly incremental backups are your friend.