Rosewill RX234 2.5" IDE to USB Enclosure for $7 with code EMCJJJC36 .
This works with 2.5" (laptop) "IDE" hard drives only (not Serial-ATA), useful if you have an old laptop with an old IDE hard drive, and want to turn its hard drive into a portable USB drive.
Rosewill USB3.0 Hard Drive Docking Station for $25 with code EMCJJJE42 .
We bought it when it was on sale for $24 a couple weeks ago.
It supports regular USB (USB2) and the new USB3.0, and works on Windows and Mac. The reviews are pretty good, with some people reporting over 100 MBytes/sec transfer rates through USB3.0. USB3.0 also supports 3TB hard drives. If you have a fairly new computer with USB3.0 ports or plan to get one soon, this seems like a great deal to provide hot-swappable storage for any Serial-ATA hard drive you have laying around.