My favorite non-RPG thing to come out of a RPG is Lords of Waterdeep. Lords of Waterdeep is a fantastic introduction to the worker placement genre of board games and it has a theme based on D&D's Forgotten Realms setting. Light euros are not the kind of games that WotC are usually know for, but they really hit it out of the park with Lords of Waterdeep. Not only is it a good use of the D&D theme, but it is a solid worker placement game in its own right. Better yet, it is a great introduction to both worker placement and strategic board games in general. It is very easy to learn, and plays quickly. It also is very easy to set up, something that you cannot usually say for these kinds of games. This is a great gateway game that can lead to other fantastic games like Manhattan Project and Yedo. My wife and I have played this many times, both the cardboard version and the excellent iOS application.