PZ8 WWII is a set of free wargames rules for fighting battles of the Second World War using 6mm (microarmor) wargames miniatures. They’re at the 6mm Yahoo Group.
PZ8 1950-69 is a set of free wargames rules for using 6mm miniatures to refight battles of the mid to late 20th century. They’re at the 6mm Miniatures Yahoo Group.
Kampfgrupp OST is a simple Hex based Operational level WWII game circa 1944-1945 East front.
Hunters on the Shoreline is a set of free wargames rules for playing WWII coastal naval actions using 1/600 miniatures. It’s available from PT Dockyards.