The solution? Setup your PC as a media server and connect your PS3, Xbox 360 or both to it and stream content to your TV.
This walkthrough will deal with Windows Media Player and the Zune software. It is possible to use others. You can also try out SimpleCenter. I haven't tried it, yet, but it looks nice.
In Windows Media Player 11:
- Toolbar -> Library -> Media Sharing
- Check "Share My Media"
- Select "Scan for Media Servers". (same for both the PS3 and Xbox 360)
- Allow the connection from the unknown device (there should be a pop-up bubble).
In the Zune software:
- Settings -> Software -> Sharing
- Follow the same steps for WMP 11
You will now be able to stream your content to the console for display on your TV. Obviously, your PC needs to be turned on...
A note to Zune users: You can also plug your Zune into your Xbox 360 with the Zune USB cable. Your Xbox 360 will pick it right up as a media source and allow you to play your music.
Update: I tried out SimpleCenter and it works great. It doesn't do anything extraordinary to make me use it over the Zune software or even WMP, but it has a very nice UI and media sharing is very simple. The setup was also straightforward and required almost no real interaction from me to import all of my music, pictures and videos into the SimpleCenter libraries.