Charge! is a set of fast play ancients rules from Tom Hinshelwood.
Miniatures Rules
Sellsword Fantasy Skirmish Rules
Sellsword is a set of free wargames rules for fantasy skirmishes. From the website:
The game is designed to allow 2 or more players (but usually 2) to play in head to head battles with different but generally equal warbands. Each warband is made up of men and monsters who share core ideals (their faction) that guide their conduct. A warband is constructed by first adding to it units, based on their victory point cost, then adding modifications to those units having prerequisites to carry them to round out the victory point total. In some scenarios, the overall fantasy level is limited as well. Then, a player simply picks miniatures from their collection that match the brief description on the stat card, and the two warbands enter a battlefield. Combat proceeds in rounds, with each unit taking a turn in each round. Units move, make attacks, and deal damage, dropping their enemies. Once you’ve played a few times, matches resolve in about 40 minutes.
Dinky Dau Vietnam Rules
Dinky Dau is a set of free wargames rules for skirmishes games set in Vietnam.
Hot Trod and Red Hand Border Reivers Rules
Hot Trod and Red Hand is a set of free wargames rules for sixteenth century Anglo-Scottish border warfare.
MuTaTioR Le choc des MuTaNs (Mutants: Shock of the Titans)
MuTaTioR Le choc des MuTaNs (Mutants: Shock of the Titans — that’s as close as I can get the translation) is a set of free wargames rules in French for combat between mutants in an arena. Google translate does a pretty good job of making sense of this in other languages. One great thing is that it includes rules for creating mutants — shades of Gamma World and to some extent, GW’s Realms of Chaos (I vaguely remember creating mutants for that game).