Klamp Electronics via Amazon offers the refurbished Apple Mac Pro Intel Xeon 3.7GHz Workstation, model no. FE253LL/A, for $2,099.99 with free shipping. That's $449 under our February refurb mention and the lowest total price we've seen. (It's also the best deal now for a refurb by $99; Apple Store charges $2,549 for a refurb.) It features an Intel Xeon E5 3.7GHz quad-core processor, 12GB RAM, 256GB flash storage, dual AMD FirePro D300 2GB video cards, 802.11n wireless, Bluetooth, and Mac OS.
Note: A 1-year warranty applies, although it's unclear who backs it.