Building a cheap computer

  Okay so basically I know I need a motherboard with...

At least an 800 Ghz processor
SDRAM with a min of 1G total RAM
A coolong fan

   Is it unealistic to expect this at 100 bucks or less?  I'm tempted to go with a celeron chip but I heard those are pretty crappy when it comes to playing games and multimedia.

You can probably get the mobo with an 800Mhz proc for free.

The RAM might cost.

for free you say?  do explain?

 When I said 1 gig of ram, I meant the capability to handle 1 gig of ram, not that it came with 1 gig worth of SDRAM chips already in it. I have a couple extra ones lying around, I just need a new motherboard to jam them into.

As I said, for free. Almost nobody is interested in sub-ghz machines anymore. If you have some friends in the right places, or wander around places where there are a lot of computers (like your local uni), it's pretty easy to pick up these machines as they're junked.

You can probably get them for a few token dollars at swap meets and the like as well. Also check out recycle stations, or watch out for computers sitting on the curb (this is really common near student residences when uni finishes for the summer).