The other day I was re-installing windows and half way through encrypting the drive with TrueCrypt I wondered what if I encrypted with bit locker afterwards? So I decided to try it and see what would happen. To my surprise it actually works. I notice a slight amount of lag, mostly when booting, but besides that it actually works flawlessly. This means that if someone wanted to they could double encrypt their system HDD and protect them selves even more (although over-kill). With this setup if any vulnerability were to be found in one of the programs the other would negate the effect completely. You also get the added use of tokens and memory wipping that TrueCrypt has yet to provide. As I said extremely overkill but it IS possible to do this. Just thought someone may enjoy trying this.