One of my fav programs right now is TrueCrypt. http://www.truecrypt.org/ This wonderful, free software creates a virtual encrypted disk within a file and mounts it as a real disk - or encrypts an entire hard drive partition in the same way. Its dead simple and works for XP, Vista and Linux. Its ideal for securing your user data on a laptop. I don't know about you, but if my laptop gets stolen the last thing I want is someone getting their grubby little hands on my stuff.