Clearly as far as snooker goes no one comes close to Ronnie. When he's amongst the balls his cueball control is unbelieveable, makes the game look so easy. Just wish he could keep his head together and win stuff more often.
When I was growing up I used to love to watch Jimmy White and still cant believe he never won the world championship. Also had a soft spot for Drago when he was still a force at snooker, he's a clip I found of him making a century in 3:30 against a young John Higgins :
http://www.youtube.com/watch?v=HVaUhlgIa6U