There's a snappy port of the Cheapass game Button Men available for, I think, $.99.
Link here:
Button Men - Beat People Up
For those not familiar, it's a very cleverly conceived fight-themed skin over an alarmingly simple abstract strategy game played with D&D style dice. Seems they have expanded the game a good deal, but for your dollar you get a lot of different setups and a decent-enough AI, it appears. Dollar well spent, I'd say.