Zone of Enders (favourite), MechWarrior (so old school LAN party days) and Armored Core... for mech games. I can't think of anything recent and great except maybe Metal Gear with Raiden cyborg sexiness. XD
Oh and how could I forget this.... Titanfall, that just came out. Xbox only AFAIK and I don't have Xbox. QQ
Kinda like a Call of Duty with mechs.
ETA:
Video for Titanfall