If You Build It They Will Come

Engadget has a tutorial on building a cheap media player.

Of course they assume you have:

• a laptop with S-Video or RCA TV out, a mini-itx box, or other PC with video out
  
• RCA or S-Video cable
  
• mini stereo plug to RCA adapter
  
• ability to burn CDs
  
• something good to watch
  

but I guess good geeks will have this (and more) all within arm's reach.