Quiet Media PC made from Junk
 

This article is intended for people like me who already have a noisy system they want to make quieter. For someone shopping for components to build a media center from scratch, the part about fan control is irrelevant as most decent mobos already have thermal fan control built in, as do modern PSUs. In general, the cooler you can keep your PSU and components, the slower the fans will run and the quieter it will be. So this style of box is still worth thinking about.

http://www.silentpcreview.com/article736-page1.html