MCE based home automation software! has an interesting story on a Windows Media Center Edition plugin that allows users to control their "Harmony" enabled appliances. From the link:

New Features of “My Home” include:
o Ability to load Scenes, access Events, Macros and other Harmony Settings.
o The ability to dim lighting with the MCE remote.
o Fully scalable to work with any screen resolution, standard or widescreen.
o The plug-in also allows use of the viewport facility in MCE.

The intelligent software learns which devices and rooms are used most often and display’s them in the new Quick View home screen. This allows quick access to all the most used features of Harmony. The plug-in has been developed with usability and functionality as the most important issues in mind...

This is sooo cool!  I want to be able to write a macro that will dim my lights, turn on some Barry Manilow, and engage the "my pictures" screensaver with photos of a fireplace :)