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.
Escaramouche is a set of free wargames rules for skirmishes in the Pike and Shot era. It’s designed to be played with perhaps six figures per side.
No Dachi is a set of free wargames rules for Samurai skirmishes.
Richard Bradley of the Tyneside Wargames Club offers a set of free wargames rules for skirmishes in the English Civil War.
And One For All is a set of free wargames rules from Eureka Miniatures for swashbuckling adventure in the tradition of the Three Musketeers.