We bought a stack of Dell servers off of eBay for work. The price was great, I think it was about $3K for 20 1U Dell servers. 8GB RAM, Dual Xeon, and 4 SATA drives in each one. They even have a MegaRAID on board, how perfect is that? I installed FreeBSD 9.1 on two of them, used ZFS, and they are both running nicely. We then decided to stand one up as a Windows 2003 R2 server, because everything was going over so well.