It would need to be a lot more intelligent to be perfect, but there are probably a few keywords you can use to filter out the bulk of prizes you don't want.
I'm not sure how the filter would work to catch something like:
-tickets to Carrot Top at Golden Nugget Casino in Atlantic City
So I'm pretty sure there's going to always be a modicum of human involvement in the claiming part. It could auto reply with some PO box address maybe. He did note sometimes he didn't receive the item (ex: 'tupaware').
