A broken 360 is worth like $30 credit towards a PS3 slim. BTW The Slim are now out in America! Trade in those 10 RROD/E74 360s you have lying around for a PS3 Slim! :D
That would actually be pretty hilarious--seeing someone walk into a store with 10 360s and saying "I'd like to trade all these for a PS3."
Something like that would also make for excellent marketing potential.