Matt Fritz offers a set of fast play miniatures rules for World War II Aerial Combat.
The Great War
World War I Dioramas
Eye Candy time.
Mike Cooper has photos of several World War I dioramas that he has made. There’s Austrian Artillery, one of the Great War in Palestine, a trench mortar and a gas attack model.
Entrenched WWI Rules
Entrenched is a set of free wargames rules for games set in the First World War.
Canvas Eagles WWI Dogfight Rules
Canvas Eagles is a set of free wargames rules for WWI Dogfights
WWI Guns and Tanks Photos
Rudi Geudens has a page with photos of World War One guns and tanks from the Belgian Royal Museum of the Army and Military History in Brussels. Photos such as these are always useful when painting your wargames miniatures.