if you are going sell it, sell it on ebay for bidding. and a put a starting bid for $100 cuz that at least what you want
Or just sell it on craigslist and have it gone within hours ;p I always sell locally I want my old tech crap GONE. Ebay is a good choice though if you want to wait and make more moneys.
EDIT: Not that your 660 is old tech crap, bc it certainly isn't!