So, here's a description of the flash drive in question: It's a 2 GB Sandisk Cruzer Micro. It's been partitioned into two 1 GB partitions with Disk Utility, one formatted with HFS+ for Mac and the other with FAT for Windows. What I'm looking for is some program to password-protect both partitions, so that when someone tries to access one of them they are prompted for a password. Whatever program(s) does this must be able to run completely off the USB stick, without any need for installation of anything on the computer the flash drive is plugged into. Any suggestions?