WWII Platoon Commander applies the mechanics of the Blitzkrieg Commander rules to a skirmish system.
Miniatures Rules
War of Spanish Succession Supplement for Black Powder
& Blenheim Palace is an unofficial supplement for the popular Black Powder rules.
Road Cycling Tour Miniatures Game
Fog’s Soldiers offers a set of free miniatures rules for Road Cycling, and not incidentally, a line of miniatures to go with it. You don’t need them, though, because you also can download printable rider tokens.
Jousting Tourney Rules
Al Hewitt and Ric Willey offer Jousting, a set of free wargames rules for medieval tournaments.
Anticamente Hex Based Ancients
Anticamente is a set of free hex based rules for ancients offered by TB Line Hobby Wargames. It’s a very nicely presented set. The authors write:
The Rules will let you replay the epic battles that took place from Ancient times right up to the early Renaissance period with an “area-based” approach. The use of hexagons will allow you to use three dimensional scenery in complete synergy with the rules without one aspect penalising the other. Anticamente does not pretend to simulate battles; the unknowns are many and modern deductions are often based on hypotheses which, in turn, derive from a few confused and, at worst, contrasting sources. Instead, after some play tests and objective deductions, Anticamente attempts to suggest the reasons why some situation occurred.