WTF is FreeOTFE and why would one use it instead of TrueCrypt?
FreeOTFE is an On The Fly Encryption application.
You can use it instead of TC because it doesn't need to be installed, at least the Portable Explorer version doesn't(otherwise it requires admion permissions).
Truecrypt does not need to be installed either. You can easily create a TC Volume on an flash drive, mount it when needed and carry the Truecrypt program itself on the same flash drive.