Encryption with USB stick instead of password?

[Linkex]

A fairly straightforward question hopefully, but is there such a thing as hard drive encryption software that uses a USB stick instead of a password? e.g, I go to my PC, plug in USB, turn it on and it boots into the OS without further prompts, but without USB, won't boot at all.

Because of a use case where physical security is trusted more than information security if you must know (Someone always asks)

 

[Bry]

Bitlocker can do this. You need windows 7 ultimate or windows 8 pro though.

Bitlocker you can use:
tpm (chip on motherboard), pin (startup password), startup key (usb memory stick)