Lancer Runolfsson offers Six Page Napoleonics, a set of simple Napoleonics rules for a game in four to five hours.
Miniatures Rules
Ironclad Draughts One Page Ironclad Rules
Ironclad Draughts is a set of one-page rules for playing out battles between ironclads.
Air War 1917
Air War 1917 is a barebones — and free — version of Wessex Games’ AirWar: 1918 biplane combat rules.
Heroes of Victoria’s Empire
Heroes of Victoria’s Empire is a set of free wargames rules for heroic actions in the colonial era.
Forge of War Science Fiction Rules
Forge of War is a set of free science fiction skirmish rules from Craig Cartmell. He writes that they were born of frustration with the Warhammer 40K rules from Games Workshop.