Man, it's AMAZING the performance you can get for your dollar right now. My son (the gamer) needed a system upgrade and I used part of my "Dubya" tax rebate to order the parts tonight. Between discounts and rebates, I was able to put together a killer box at Newegg for a final cost of just over $700, delivered. Here are the specs:
The Geforce 8800GT 512MB video card will give him great graphics performance, and the Intel Core 2 Duo E8200 processors overclock like a mother! We should be able to get 3.5GHz clockspeed or better on it, since these 45 nm Wolfdale core processors run so cool. Really looking forward to building this puppy and seeing what she'll do this weekend!
5/20/08 UPDATE: I looked into the stock CPU cooler that comes with the E8200 and it was pretty pitiful looking, so decided to add the very popular Arctic Cooling Freezer 7 Pro cooler to the mix. It was an extra $34, including shipping, bringing the total final cost to $716. I'm thinking 3.8GHz looks very possible now....