If you've managed to shoot, plunder, stab, bowl, punch, clothes shop, kill, and screw your way through all of GTA IV and are looking for a new challenge, why not download the demo for the stunning Bus Simulator 2008.
Not convinced? What if I were to tell you that it's not some run-of-the-mill U.S. bus simulator--it's a GERMAN bus simulator! Now you are convinced. Enjoy. Tschuss.