In a press release issued today, Corsair announced the release of new line of secure mobile storage. Their "Flash Padlock" units are USB drives that include an integrated hardware encryption and authentication, which encompasses a variety of different functions. It includes automatic "locking" after unplugging as well as the ability to lock it with a 10-digit pin, and others:

With its simple touch-pad security PIN entry system, Flash Padlock can be unlocked quickly and confidentially for use as a standard USB flash data drive. Flash Padlock is impervious to "brute force" hacks or keystroke loggers that would defeat a software secured USB flash drive.
The device is supposedly compatible with all 3 major computer platforms, including Windows, Mac and Linux. That makes the device somewhat unique, and the price isn't all that bad, with the 1GB units starting at $29.99. You can read the full press release at Corsair's site.