hmm well since im new i havnt got that much yet and dont know what BTC people look at as collateral.
Things that might be interesting ?

i got few cheep stocks on btct.co ( found out about this site few days ago )
i got arround 30 PS3 games ( like brand new )
i got a starcraft 2 wings of liberty cd-key  (unused)

If this is wrong please give me some other examples