I have 2:
one is an AMD Athlon Xp 2200+, and is 4 years old. works great, except I had the RAM replaced under warranty in the first year, and the CPU fan failed a month or so ago. Ive since replaced it, but its the wrong size. I have since installed Win 2003 on it (in addition to XP Pro and Ubuntu)
the new one is a Compaq P4, came with Vista Basic, but have since installed XP Pro again (Vista basic can't join a domain
). I bought it just after the fan in the old one failed, about a month ago.
I love my MSDN-AA licences