David Heading offers a set of free wargames rules for Renaissance Naval Battles.
rules
On To Waterloo Napoleonic Rules
On To Waterloo are a set of free wargames rules based on the On To Richmond American Civil War rule set.
Argad Medieval Skirmish Rules
Argad is a set of free wargames rules for skirmishes in the dark ages and for pirates in the 17th and 18th centuries.
Victory Without Squares
Victory without Squares is a modification of the Victory without Quarter English Civil War Rules System. Both are free wargames rules, with the “without squares” version using inches, rather than squares for movement and range.
Bar Brawling Rules
Bar Brawling is a set of skirmish rules for wild west barroom brawls.