After 3 or so years or so of service to my household, my Linksys WRT54G version 1 router finally died out. I was shopping around for a new one when it hit me that I could just build one myself. So I started looking around my house for parts. After a trip to the computer Pick-n-Pull in my garage, I dug out an old Gateway PIII 500 that someone had given me. I also found some more ram (128x3) to put into it, as well as a 20gig hd. I harvested 4 identical Linksys 10/100 nic cards, and a 52x CD-Rom drive.
For the software to drive all of this, I found IPCop, a linux distro that will turn any computer into a router-firewall. Also, because this is open source, you do not have any of the restrictions that a normal store-bought router comes with from the factory. This means that if you are an avid Bittorrenter, this is the best solution to get the fastest speed. The only problem at this point is that setting up wireless on it is sort of difficult, but that is next on my list.
After you install all of the hardware, and run the setup CD, you can configure it just like any normal router by accessing it through any browser. For now, I got it to run right and it is managing the entire network. The only problem I am having right now is that when I set up PPPoE, it doesn't seem to want to try to make my modem connect to the DSL network. I ran out of time last night to solve the problem, but hopefully I will have it fixed soon.