I've never used it for gold or for cats but I have used it to sell the various E-scrap I accumulate. I've had mixed luck with buyers there but the site itself is great. The website address is www.recycle.net you can sell pretty much any type of scrap on there but the buyers are looking for tonnage, not pounds.
To the computer recyclers out there, there were a few companies advertising on this site that they would buy used and untested or broken CRT's for recycling. I wouldn't expect to get more than $50.00 per pallet but one guy in my area said they even pay for the shipping. If they'll take my scrap monitors for a buck a piece and pay to haul them off, I'm more than willing to throw them on some pallets for 'em. I told the company purchasing them they had been sitting outside in the rain, sun and snow and he didn't care. The web address for that company is plasticnation.com and I haven't sold anything to them yet, just verified that they will buy what I have so I couldn't say what it's like to actually do business with them.
a side note on where else to find cats cheap.....Craigslist and the catmax.net pricelist. There is always a car guy on CL who will be happy with that price, especially if you're picking it up.