NeweggFlash offers the refurbished HP 6300 Pro Intel Ivy Bridge Core i5 3.2GHz Small Form Factor Desktop PC for $249.99 with free shipping. That's $80 off and the lowest total price we could find. (Merchants charge at least $350 for a slightly different refurbished model elsewhere.) It features an Intel Core i5-3470 3.2GHz Ivy Bridge quad-core processor, 8GB RAM, 2TB hard drive, DVD burner, USB 3.0, and Windows 7 Professional 64-bit. Deal ends May 29.
Note: A 90-day warranty is applied, although it's unclear who backs it.