The World War II RPG by Mikko Kauppinen is designed as a simple game that is deadly to low level characters, but that allows more powerful characters to do very cinematic actions. Characters have three attributes and a number of skills. Action resolution is done by rolling 1d6, subtracting the result from the relevant attribute and adding one. If the result is more than zero, the character has succeeded, and bigger numbers mean greater successes.
WWII
Red Flags and Iron Crosses
Bob Corderey offers Red Flags and Iron Crosses, a set of free wargames rules for playing World War II games in 20mm. The rules focus on small actions between Soviet and German forces.
MG-42 Two Hour Wargames Introduction
MG-42 is a set of free wargames rules designed as an introduction to Two Hour Wargames’ Reaction system.
East Front Sniper Game
In East Front Sniper, each player acts as a World War II Soviet Sniper, competing to rack up the most kills.
Warhammer World War 2
Warhammer has been adapted to every period I can think of. Here’s a version called Warhammer Panzer Battles