If you don't have terrabytes of data, and you have good upload bandwidth, then at .15 per gig for multiple, safe-room offsite storage, then Jungle Disk is certainly up there as one of the top solutions. I've been using it for over a year. The software is easy if inelegant, Amazon's customer service is very good, and I've had not one technical problem.

Having two tbyte drives in different places seems like a decent alternative. That said, it's not infallible compared to multiple redundancies in multiple safe storage sites. Why? I've been using Mac's since the first one rolled out and mass storage was a 20 megabyte scsi drive the size and heft of the American Heritage Dictionary. Since owning generations of different drives made by different manufacturers, I've found that they fail more often than the average rate of 15% within three years. Even worse, at least twice in my life, flood and fire have destroyed my equipment. If it weren't for offsite storage of my most precious photos and files, I'd be offsite in some safe room--in a straight jacket.

So to the good soul who asked why not use Apple free solutions, I do use them. And I use Jungle disk for the above reasons.

Cheers.
Evan Mitchell Stark Phd