The title says it all, here are some of the ones I have had my eye on, but feel free to suggest others. Price wise lower is better, I'd like to pay $450 or less. But these things go on sale ALL the time so even if one is more it might plummet.
http://www.newegg.com/Product/Product.aspx?Item=N82E16824009554
http://www.newegg.com/Product/Product.aspx?Item=24-236-347
http://www.newegg.com/Product/Product.aspx?Item=N82E16824005533
http://www.newegg.com/Product/Product.aspx?Item=N82E16824160162
http://www.newegg.com/Product/Product.aspx?Item=N82E16824009554
http://www.newegg.com/Product/Product.aspx?Item=24-236-347
http://www.newegg.com/Product/Product.aspx?Item=N82E16824005533
http://www.newegg.com/Product/Product.aspx?Item=N82E16824160162