MCW6000 flat base
Comes with the xeon adapter plate but a replacement plate can be ordered from various places like:
www.frozencpu.com for $10 or less if you want to use it in a non xeon aplication.
asking $35 shipped
here's a pic of it next to the mcw5000
Compatible with the following just might have to get a different top:
P4 socket 478 processor
Xeon™ socket 603,604 processors, including "Nocona"
Athlon 64, Opteron "K8" socket 754, 939, 940 processors