MegaMacs offers the refurbished Apple Xserve Intel Xeon 8-Core 3GHz Server, model no. MA882LL/A, for $549.99 plus around $47 for shipping. That's the lowest total price we could find for a similar configuration of a used unit by $254. It features two Intel Xeon 5400 3GHz quad core processors, 4GB RAM, three 1TB hard drives, and Mac OS X 10.6 Server. Deal ends March 19.
Of note: A 30-day MegaMacs warranty applies.