Warzone Modern battles is a set of free modern Wargaming rules for 1:72 or 20mm Squad/Platoon games.
Rules: Modern
PZ8 1950-69 6mm Wargames Miniatures Rules
PZ8 1950-69 is a set of free wargames rules for using 6mm miniatures to refight battles of the mid to late 20th century.
Jihad Wargames Rules For Modern Insurgency
Jihad is Stan Johansen’s rules for modern insurgencies. There also are printable action cards and counters.
Covering Fire! One Page Rules
Covering Fire! is a set of free wargames rules on a single page. It is designed for platoon level actions and uses no measuring tape or turn structure.
Firefight 2050 Rules
Patrick Todoroff offers Firefight 2050, a set of rules for 1/72 figures in a near future setting.