A Splendid Victory is a set of free wargames rules for the English Civil War. They’re designed for 28mm figures, but the basing system is flexible.
rules
Quick Play Low Intensity Warfare Campaign Rules
Quick Play Low Intensity is a set of free wargames rules for playing campaigns set in Vietnam or similar conflicts.
Richard Bradley’s Samurai Skirmish Rules
The prolific Richard Bradley has a set of free wargames rules for samurai skirmishes.
Richard Bradley’s Seven Years War Rules
Richard Bradley’s Seven Years War rules are designed for 15mm figures on a 40mm frontage.
Richard Bradley’s Pike and Shot Skirmish Rules
Richard Bradley offers a set of Pike and Shot Skirmish rules.