I don't care about the vanilla 6800's. I'm building a SLI for 6800GT or Ultra and those are the ones that are scarce. The 6800 is on par with the 6600GT-a middle of the road card.
Alright... $667:
http://www.gameve.com/gve/stor...s.aspx?sku=VC-EVGA-057
...although a heck of a lot of people get by just fine in pretty much all current games with a single one of these... and dual 6600GTs will do even better in Doom3 and the like. How did you survive before SLI existed? Perhaps waiting a little bit wouldn't kill ya.
-S