Todd Duffee? Brett Rogers? Paul Buentello? Badr Hari comes to mind, i dont know if Fedor would win but i would be a fight worth watching. Werdum and JDS
Nobody should be suprised if Overeem get's demolished by Silva, Werdum, Barnett, Fedor, Cain, JDS. All those guy's are more than capable of knocking him cold, subbing him or beating him up. The Overeem hype is too much and he's not this all new unbeatable, unstoppable Ubereem monster that he's made out to be.
This: I'll go ahead and add Sergei to that list, him and Werdum have both beaten him before, there's no reason to think they can't do it again. Also, how do you get top 5 p4p from a guy who's losses are in the double digits at a lower weight? Overeem may well go on a tear for the next few years and secure himself a spot as the number 1 heavyweight. But until he starts fighting guys that are actually legitimately ranked inside the top 10 he is not a top 10 heavyweight.