Aside from the morning commute, I listen to 80 percent of my music on my PC. The quality isn't bad, but it isn't nearly on par with a decent stereo system.  For that you are going to need a Digital Audio Converter (DAC) like WaveLength Audio's Brick ($1,750, list).  The Brick connects to your USB port and works like a high-end external sound card. Free from the interference of the PC's other components, this is an ideal way to link up to high-end stereo equipment.

Of course, the price tag is way above what most casual can afford. (Right now, anyway) Still, I wouldn't be surprised if this type of external DAC becomes more common as more people start putting PCs in their entertainment centers. 

[[Found on MSN's TechFilter]]