I already have the 128 mb green colored Soyo drive. It works under XP, 2k without drivers. I did have to install drivers for 98Se on a machine or two. Things to note: the software that comes with it is crap. You would have to install their special drivers to password protect it or use those hot-synch features the product is advertized with. I use it as simple storage, I've heard of using programs and mounted drive stuff to protect, but I haven't done it. It's a bit on the longer side to attach to keychain IMHO.
People on FW are ordering with 2nd day shipping for two dollars more. Probably worth it. I'm still sitting on my hands trying to avoid buying this in the name of xmas gift for others. This would be such a great stockign stuffer, yet just illustrate how much a geek I am.