Outside of football:
Mark Cavendish in his prime. If the stage was flat you knew he was either going to win or crash.
Juan Pablo Montoya. Hugely quick from the get go in F1, was one of the few drivers to ruffle Schumacher's feathers.
Asafa Powell. His sprinting technique was flawless. Such a shame he always bottled it on the biggest stages.
Juan Martin del Potro. I'm not much of a Tennis fan but I've always enjoyed watching del Potro take it to the big boys when he's fit and healthy.
Alexander Rossi. For anyone who watches Indycar, he pulls some of the most incredible and daring overtakes without somehow hitting anyone or anything.