I just re-discovered Exteel (multi-player online video game where robots kill one-another with swords and guns and the like...). I had been drooling over it when it was still some unknown number of months from being released, but had forgotten about it. Someone pointed me toward it, and I've fallen in love.

Anyway, it seems like something people here might be into, so I thought I'd pass it along. Thought to do so because while I was playing I was trying to figure out how to have an experience that's anything like the video game on a tabletop and realized that the city of Mayhem would be a likely location for such a thing...

Thanks for the heads up on that:)
As for gaming it Tabletop...you might also consider Platform Command:)
Mecha and P Com were made for each other:)

The PCON expansions Red Sector and Battleground both include mecha. Red Sector includes a game to play with the mecha you build.