A friend of mine recently told me about this and I am trying it now. It was easy to setup and seems to work awesomely well. Follow the instructions and load the software on the USB drive, boot the computer with nothing but the flash drive and it will go into folding automatically. Make sure you edit the config files so you and Team MacNN get credit though!
No hard drives running, no CD drives attached, Very cool!
OOPS, I forgot to put in the URL.......
http://reilly.homeip.net/folding/usb.html