Memory maker Corsair has begun selling the Flash Padlock, a USB 2.0 flash drive with an abnormal approach to security. Rather than rely on software encryption, the Padlock has a built-in, nine-digit PIN pad, which enforces hardware barriers to unauthorized access. When removed from a computer, the contents of the drive are locked again automatically. This scheme is said to make the Padlock impervious to keystroke loggers and brute-force hacks. PINs up to 10 digits long are supported, and the drive works on Mac, Linux and Windows systems. A 1GB drive costs $30 while a 2GB drive is an extra $10.