Where is the Best Place to Buy Used Cell Phones

I like buying used cell phones on eBay. I've also won a couple in some local auctions, but general you might have to do a little work to buy a used cell phone and get a good deal.

Of course that doesn't even address if you are looking specifically for old cell phones rather than recent used ones. I have to admit, I like to keep my phones a long time and once I'm used to a good phone I don't upgrade until I have to. My cell phone is 4 years old.

I also really like some specific older models that are out of program now. You have to make sure the older phones will work with our current wireless plan. I haven't had any problem so far. I usually keep my old phones in case something goes wrong with the new one and the provider won't let me out of the contract.
Purchase Used Cell Phones

Do you have a favorite place to buy old cell phones?