Neverwinter Nights is a game by BioWare that has the rules and regulations of Dungeons & Dragons, but does it in a 3D computer game format! I think this game is very great, yet it gets boring after a bit which is it's only downside really. But, to try and counter that, they included a module-maker so that you could create your own story... almost an entirely new game! I made one of my own really quickly so that it is a training grounds basically. Have fun with it =)