WebGuide kicks the pants of Orb IMHO. The Vista SideBar Gadget lets me control my media center (view scheduled recordings, watch tv, listen to music, remote control my media center) from within my home on our kitchen PC or remotely at work.
This is a really well done piece of software. It's the holy grail of local, remote control, and streaming support for Media Center (Vista and MCE 2005).
For example, here is me controlling the audio on my MCE box from a web browser on my Kitchen PC. I can play files locally or control the Media Center via the web based remote control.
Here is a screen shot of the Vista SideBar with a list of my current recordings:
And the show playing in Windows Media Player
The setup software will configure your UPnP router to open the correct ports though. Nice.
[via Chris Lanier]