A backrest cushion that inflates and deflates on command from a computer chip. While no one is sure why it works, experts say it does. It alleviates pain by keeping the spine moving when you're forced to sit still for extended periods of time, such as on long car trips. Inventor Dr. Rowland Hazard of the University of Vermont theorizes that keeping the spine moving may feed nutrients into the damaged discs. Or, the motion may shift the load so that it is more equally shared by all the spinal muscles.