I don't have any, as I only collect 'released' stuff. I got a complete N-Gage collection:
http://www.videogamecollectors.com/g..._itemId=192136
but if I find a Asphalt Urban promo box, or a Pathway to Glory preview, especially cheap, I take it, because that's a nice bonus. The Asphalt promo I managed to get on ebay for Euro 15, can't complain there.
Having a 'full game' Payload is also nice to have, and a Super Fighter Block Battle download is also cool.