Originally Posted by VelvtRide
Windows Vista Home Premium doesn't give you an option to password protect the .zip file.
Use WinZip to create the zip file, it has the option to password protect the zip file. You should include the pkzip program itself on the flash, maybe multiple versions of it for multiple versions of Windows and MacOS, in case the computer you plug it into is too old to read new-fangled zips, or too crippled (in the case if Vista Home). Stuffit Expander is probably the easiest one here, since it's free (unlike WinZip) and has both Mac and Windows versions. Use Teh Google to find out where to download these.