External Portable HDD Hitachi 320GB

Specification:

Being sealed and secure is the key selling point for this particular external drive series. Hitachi claims that it's water and shock resistant, although it's worth reading the fine print there, especially as the weasel word "resistant" is used rather than "proof". Water resistance was measured using 60cc of liquid, which means it'll probably survive you spilling your water bottle on it, but probably not if you take it scuba diving.