The Nokia N900 seems to be able to run practically any game you throw at it. A while ago someone managed to get Nintendo games to work on the Finnish smart phone and now someone has put Duke Nukem 3D on it. As you can see in MaemoWorld's video, you control Duke using the Qwerty keypad and shoot using the touchscreen. According to MaemoWorld, you can download the game by going to the application manager on your N900 and searching for 'Duke Nukem 3D shareware'.