You can try these guys, they'll send you an email. You could probably sell it yourself for 3x what they offer.
BUT, I wouldn't do it. Let's face it. Buying BRAND NEW gear often leads to frustrating obstacles. Selling in the used market is an invitation to disaster in terms of ratings from buyers on ebay, or whomever cragislist drags up. If they get convinced you sold them bad kit they'll want revenge. (I know this because I sold a guy a Thorens turntable which he said blew out as soon as he got it home. He left about twenty angry messages on my answering machine. I called him back and said don't worry bring the turntable back and I'll refund your money in full. I had been out that night at the movies. )
Basically I landfilled my last mobo and cpu. You can say, well why not just give it away. I did that once with a psu. The person who responds is someone who really wants a computer for free. So this guy comes to my house and I give it to him and I offer to give him a ride to the nearest bus stop as he had made a nearly two hour trip to get to me. So we were talking and he mentioned that he was a felon out on parole and was trying to get his life together.
I will say two things about that. He was real nice. I was happy to help him out with a free psu. But I just decided that I didn't need to give stuff away any more because maybe the next person wouldn't be so nice. Maybe I'd give hardware to a charity but last I checked good will doesn't want cpus and psus etc.
Greg N