Sony has its own Memory Stick format, but keychain USB flash drives proved impossible to resist. The Micro Vault comes in 16MB ($49), 32MB ($69), 64MB ($99), and 128MB ($149) capacities, each of which sports a different color so that it's easy to tell them apart.
Compact, eye-catching design; software-based security, top-notch documentation and support
Password protection with Windows XP and 2000 only; no carrying case, key ring, clip, or USB extension cable; moderately expensive