Reich Star is a Science Fiction role playing game built upon the premise that the Axis powers won World War II by nuking London and New York in 1943. Generally play begins in 2134. The whole tone of the system is very anti-NAZI (a good thing). The setting is definitely dystopian. The closest thing to the good guys as far as any power are concerned is Imperial Japan and they are pretty bad. This system is fairly realistic, but playable. The combat system is very deadly, if your players are hack and slash types almost any adventure in this system is likely to kill them. One thing of note about this system is that it has the best system for handling radiation exposure that I have ever seen. In fact it looks like it could have been take out of a medical text on the effects of radiation on the human body.
If you are interested in knowing more about this system you can look at the Reich Star homepage