password protect external HDD

[snail]

ok, simple and basic.....i want to be able to password protect my external HDD eg: if i take it to a friends house i have to put a password in to access the hard drive. basically i want to be able to use it on any pc, but it must be password protected. any ideas how i can do this?

 

[LazyLion]

http://www.magic2003.net/
http://www.truecrypt.org
http://www.folder-password-expert.com/usb.html