I used to keep a lot of old computers and parts around for no real reason, starting with my very first computer in 1999, Elyham, which served me for about five years until Azmaria, built in 2004, which was succeeded by Nanoha, my current machine, in 2009. Five years seems about the average turnaround time for my computers, and even after I’ve built a new one, I tend to keep them in use as a webserver or some other project until they’re fully decommissioned.