I saw something like this a few years ago. I was in rush traffic near the DFW airport. A small pickup in the next lane over had a mattress loaded the same way. There was a man lying on the mattress to hold it in the pickup. His lane was going a little faster than mine. A mile or so down the road I saw two things bouncing along the blacktop. One was the mattress and the other was the man who was lying on top of the mattress. The mattress bounced a little longer than the man did.