Dell Optiplex 745 + Upgrades
I just purchased a 745 off of eBay for $145.
It came with a Dual Core Pentium D 3GHz, 2GB-DDR2/667MHz, 80GB SATA HDD, and DVD-Rom/CDRW.
Well I did a few upgrades to it by adding another 2GB-DDR2/667MHz, Lite-On LightScribe 24X SATA DVD+/-RW Dual Layer Drive, and a Western Digital 1 TB Caviar Green SATA Intellipower 64 MB Cache.
It's not a bad system for having a little over $200 tied up in it.
I'm thinking of buying a SSD for the operating system. It will be a later upgrade if I do.
This system will do me fine for the stuff I do on it.