The latest SDKs (beginning with 2.2, I believe), include TV-Out functionality. With a special cable connected to the iPhone dock connector, a program can send RCA signals representing its current screen contents through the iPhone->RCA cable. If you have a TV Tuner for your computer (i.e. I have an EyeTV Hybrid) with RCA inputs, you can display the screen contents of your iPhone directly in the TV viewer.