Because the computer I've been using is now six years old, my parents decided to get me a brand new Dell Dimension 3000 desktop as an early birthday present. It has a 3 GHz Pentium 4 processor, 512 MB of RAM and 160 GB of storage. This rig is much faster than anything else I've ever had. Thanks, Mom and Dad!
I'm considering joining a distributed computing project, probably either distributed.net or the Great Internet Mersenne Prime Search. Given that my new computer is so fast, the idle CPU cycles would go to waste otherwise. In any case, I can finally retire my old Pentium II box after all those years. :-)