One of my clients uses Pointsec to encrypt the entire hard drive of all machines. If you don't have the password and boot up you can't go any further. In addition to connect via the VPN there is a RSA SecureID token FOB. The security policy that was just released from this client is that the laptop can be checked, but the FOB must not be in the same bag as the Laptop.
I have not used it, but I've come across Compusec a freeware whole hard drive encryption.
I have been using Truecrypt on my personal desktop at home for my financial info, etc. I am very pleased with it.