I agree with drpootums. You can actually order the card from Bestbuy on line for $399, although it's probably out of stock, so it might be a while before you get it. Still, it rocks, and it's practically an ultra (about 25MHz shy). Another good choice would be the Gainward Ultra/2400 Golden Sample, which is a similar card, overclocked, I think it's actually running at ultra speeds.
Oh, yeah, and if you can find an X800XT (non-platinum edition) it's supposed to MSRP for $450, but I've not seen it very many places. It should perform roughly on par with the overclocked 6800GTs I mentioned above.