Pomota

Pomota -- for POstMOdern TActics is an abstract set of miniatures-like rules, using a chessboard as the playing field and (usually, though not required) chess pieces as the miniatures. It provides a set of rules for movement, combat, knock-out and elimination, and a points system for both evaluating wins and using the variable and specialized powers of the pieces.

Two possible "armies" are supplied, but it is clear that the idea is that this could be quite extensible.

Full rules at: http://www.luchacabra.com/?p=33