They don't get nearly enough slaps, so...
VALVE. For the Tank in Left 4 Dead. What makes games great is their dynamics due to skill, "mis"use of mechanics, and just the ideas players comes up with. This is what led to things like grenade-jumping, spawn-camping, and all sorts of map attack strategies. The Tank completely forgoes this field of game design by giving you a "rage meter", which as was specifically stated in the developer commentaries, was SPECIFICALLY DESIGNED TO MAKE PLAYERS PLAY A CERTAIN WAY. Heck, ALL of the infected forego a lot of potential sneak strategies by making them as loud as your obnoxious roommate. Is it not awesome that, if I move well, I can sneak up on a Scout while playing as a Heavy in TF2?