One of the first and best games I've ever played was mechwarrior 2. Nothing fancy, just good old mechanized combat. It's hard to beat a good mech game, even if it had completely untextured polygons.
I've picked up a copy of mercenaries, got the mech packs, and got this mektek expansion. I've been playing it quite a bit lately, and it has pulled me away from the good but somehow mediocre doom 3.
Anybody else here play? If so, what mechs/configs do you like to use?