I've recently heard of swappa, but never used it. Looks like they have some good values on games here, I'm gonna have to keep them in mind in the future.
On a side note, I am glad there is another outlet to sell games, as ebay sucks and amazon started limiting seller privileges for individual sellers that don't pay.
One of the really cool things about this is that the winner could create more raffles or giveways with the $250, or just gift games to people who don't have much. I believe Reddit has places to do that.
Anyway, that's just me thinking out loud via text.