Honestly, the best guys I've ever played were the ones over at rtsprofessional.com

They play on all severs to my knowledge. Although I formally played against them in the fansite tournament, we found that we actually played against each other in warcraft 3 a few years ago. The things these guys have done are truly genius and innovative. Who else but the fellas at rtsprofessional would win a warcraft 3 game with a peasant/militia army?