The gold bar I use as a doorstop.
Seriously, I wouldn't sell that (largely because it doesn't actually exist). I'm not sure what I'd sell - it's probably safe to say that most things I have that would fetch money fast are things I wouldn't want to sell because I use them. Things I don't use as much are more like family items, most of which aren't worth a lot of money and even the ones that do have some value probably wouldn't sell fast.