Chris Kemp has a mini campaign for his Not Quite Mechanized rules.
Miniatures Rules
Tac Ant Combat Simulation
Tac-Ant is a set of free wargames rules for battles between hills of ants.
Seriously.
Late Roman Lion Rampant Variant
The I Live With Cats Blog has a variant for Lion Rampant featuring Late Romans.
Battle of Britain Rules and Playing Pieces
The Battle of Britain is a complete strategic game for refighting the epic battle of 1940.
Battleshift Space Fleet Combat
Battleshift is a set of space fleet combat rules for big fleet battles.