Inquisitor was game produced by Games Workshop set in the Warhammer 40K Universe. Curiously, it used 54mm figures.
The game is out of print, but a rules archive is at the link.
rules
A Fistful of Honey Cowboy Bear Rules
Eureka Miniatures offers a one-page set of rules for playing wild west shootouts with its teddy bear cowboy figures.
Star Wars Full Thrust Rules
Full Thrust is an excellent set of starship combat rules — my personal favorite, in fact. Here are a set of modifications and statistics for playing Star Wars battles.
Thumbs Up, Thumbs Down Gladiator Rules
Thumbs Up, Thumbs Down is a set of free wargames rules for gladiatorial combat. The rules are designed for up to ten players.
Dinky Dau Vietnam Rules
Dinky Dau is a set of free wargames rules for skirmishes games set in Vietnam.