Portable, Direct Attached Storage: does such a device exist?

Solution 1:

Take a look at TapeSucks.com. I am using the 2 Bay Tandem AMT 1U rack mount system with 2TB drives. I take home one of the drives every night for backup. This does not solve keeping backups for archiving purposes, however this does solve our need for disaster recovery and deleted files for the last year.

Solution 2:

If I'm reading what you're looking for right, you'd want something like this from Buffalo. It's a 4-drive external unit that has USB and e-SATA capability with RAID functionality. We use this in house at two of my sites, and I haven't had any problems with them. Standard YMMV disclaimer applies.

Solution 3:

This looks promising: no redundancy and 2.5" drives would be welcome, but this is certainly a step in the right direction, at least from a portability/physical durability perspective. And with a regular disk rotation/replacement policy (based on number of write-hours and/or elapsed time), I could see this functioning quite well:

http://www.lacie.com/ca/products/product.htm?id=10382