Gale Sayers was a pretty good athlete in football. He could do it all as a running back in the 1960's and it is unfortunate that injuries cut his career short. Another name I would throw out there is "Bullet" Bob Hayes who was inducted into the NFL Hall-of-Fame this year. Bob was an Olympic athlete who won two Gold Medals in the 1964 Olympics and then went on to the NFL where he helped innovate the Wide Receiver position. These two don't have the same star power as some of the others, but they were still greats.