What is the cheapest way to add an external video input (for display purposes) to the iMac? I just got my son a 20" iMac for college, and he was wondering if there is some easy way that he could hook his video consoles up to use the iMac's screen, instead of having to carry a separate TV with him (dorm rooms are really small). Anyway, he doesn't really need TV input or PVR capabilitues, or recording capabilities, but just some way to display Composite or S-Video inputs on the screen. I have found the Elgato TVWonder USB 2.0 which should work just fine, but has many extra features that we don't need.