P133 64mb/3.4gb Linux Distro
I've tried Redhat and Slackware, and they are a bit slow on my P133/32mb/6.4gb machine. But linuxfromscratch.org told me how to create a fast system from source instead of binaries. My customized system compiles a default Linux kernel 32% faster than Slackware 9, and I know how the whole thing is put together, since I did it myself. Check it out.