The Water Margin is a set of free wargames rules for oriental skirmishes.
rules
WWII Plastic Skirmish
Brett Drake offers a set of rules called WWII Plastic Skirmish, which are — obviously — rules for playing WWII games with plastic army men.
What more could you want? Your favorite childhood toys. Dice. Mayhem.
Burrows and Badgers Rules
Burrows and Badgers is a set of free wargames rules for tabletop adventures with bands of anthropomorphic animals. There’s also a supporting set of miniatures.
WWII Simples Miniatures Rules
WWII Simples is a one-page set of free wargames rules for WWII Skirmish games.
Generic Space Combat 2
Generic Space Combat 2 is a set of free wargames rules which allow players to design their own ships.