Very Portable External Hard Drive, any reccomendations Options

[evolution]

Hi

I need an very portable ( ie not nor standard size external hard drive eg ice cube) that has
FW 800. 7200 rpm, 100+ gigs and can be powered by usb from the computer.

I record on the go and intend to have my software on my macbook pro and my sample sounds (bfd,mach five etc) on the very portable hard drive. I've searched the internet shops with little luck

Any ideas/reccomendations

Thanks!

Ade