Does anyone know how I could use my iMac as a TV? The input from cable or satellite TV comes into my DVD recorder. The recorder takes care of changing channels. Its video outputs include regular video (RCA jack), S-video (or "component video"), and digital video (coaxial). This is the reverse of what I understand the AppleTV does, since it takes what is on the computer (say a downloaded movie) and allows you to show it on a TV. It should not be too difficult to engineer the reverse. I can record something off the cable on a DVD and put the DVD in my Imac and it plays perfectly. But I want to be able to use the Imac as a TV in real time, without the saving to DVD. Any suggestions? Is such a gizmo available somewhere? Some kind of software that would allow it?? I don't need sound as the audio out on the DVD recorder go to an amplifier and to external speakers. So I only need video.