From the Godfather of American Wargaming, Jack Scruby, comes the Rules For A 30 Years Wargame. We have the people at Historifigs to thank for offering these free reprints of classic wargames rules.
Scum of the High Seas is Rudi Geudens set of hex-based. card driven rules for playing games of Pirates on the high seas. Like others in this series, they’re based loosely on Richard Borg’s Battle Cry system.
The Lord of the Rings Yahoo group has army lists for playing a Aztec v Conquistators variant.
Jim Wallman offers a set of free naval wargames rules called La Felicissima Armada. It’s a Spanish Armada naval game designed to use 1/144 plastic ships on the floor.