My old ASRock socket A motherboard just died and found this cool motherboard for $20. I already have the DDR from the old system and there's a Celeron for $40. It even has onboard video and audio I believe. All for $20 is a steal. My old ASROCK was my trusty fileserver running samba, AMP, etc. and OBSD 4.0. I'll keep you posted on the rebuild.
http://www.newegg.com/Product/Produc...82E16813186129
EDIT: It's out of stock at the moment.