Over the past year USB flash memory drives have been showing up everywhere. Especially around campus. Some of the uses were obvious - moving files from home to lab to work, etc. This would be very handy, so I did a little research and found the Lexar JumpDrive line. The JumpDrive Secure intrigued me because it included password protection software compatible with both Mac OS X and Windows. When CompUSA had a sale, I picked a 128Mb example up - it's been on my keychain ever since.
I've used this thing even more than I thought I would. It works perfectly for doing programming/modeling in the engineering lab and transporting the code back home to include in reports. I put my presentations on it as a backup or to load on the computer at the presentation venue. I use it to move photos from the lab microscope back to my cubicle desktop at work. I carry a few choice mp3's around to listen to when given the chance. The cross-platform ability has worked flawlessly, regularly shuttling files between my Powerbook, Win2k Desktop, and even a Linux box with a little fussing.
This thing is also durable with rubberized sides and a metal ring for keychain attachment. The only negative I've found is that because it is so wide compared to a lot of competing drives, it hogs more than a single USB port by physically obstructing adjacent ports both vertically and horizontally.