From your post I understant that you don't know exactly what you want to do, but you would want to build a cluster. You could try http://bccd.cs.uni.edu/
. This is a live CD that comes with some intereting cluster tools. The one I tested is openMosix that moves applications transparently across you cluster. (but I didn't tested from that cd, although some other people said it work fine).
There is a lot of documentation around about grids and clusters, but beware it can be uninteresting if you don't have something to do with it. (I don't think quake will run faster).
Hope it helps, and tell us your impressions of the experiment