The only issue with truecrypt traveller mode (that lets you run truecrypt off a USB drive) is that it requires a driver to be installed on the computer. This driver allows the encrypted file/partition to be mounted as a drive.

So, in order for it to work you either need
1) Administrator access to the computer
or
2) Someone w/ admin access to install the driver on the computer (only needs to be done once)

Note: This is assuming you use XP