An idea that came to mind which I think can be very cool, is to use my DIY wallpaper technique for a geeky, chic look, showcasing retro video games such as, space invaders, or pacman.
The same exact technique can be used, but with a different template and probably several colors of contact paper. The following images can be used to create your templates:
If going with the pacman design, it would be fun to use stick on toy eyes, such as these on ebay:
While searching for images I actually came across a company on etsy that does a smaller version in wall sticker form:
Boys this idea would be perfect for a game room. Keep in mind however, this look will only look good if done right. Size and colors need to be harmonious with the rest of the room. If you would like help with the exact design, feel free to send me photos of your room and I will be more than happy to design something for you.