Not too many these days since I've gone mainly digital. The amazing thing is some of the old one's have become collecter items, and can fetch a pretty decent price. Others that you might think would be worth a good amount won't bring much at all. I think a lot depends on the build quality, & of course the number that were made.
The great thing about it tho', if you want to shoot film you can find some hard working gear very cheap these days. The bad news being if you have gear it has to be in like new shape (and I mean not the smallest blimish anywhere, including all boxes & accessories that came with it new) for it to bring a decent price. So selling is hard, but buying is great!
You can get a rough idea (if you downgrade by a couple of steps from what you'd normally think) by looking thru'
http://www.keh.com, which is one of the larget used dealers around. There's a guy named Ken who works in sales who is great. I deal with them pretty regular since I'm only about 10 miles from them. No.. I'm not on commision! But I get anything used from them when I'm looking for personal gear.
About the only camera that's sitting right now that I have, is my old Voightlander I've had for years. I still might have it gone thru' and shoot with it later on (if I get time to start shooting a lot again). I guess on second thought, most eveything is getting a little dusty around here at the moment!
Great thread tho', hope more begin to post to it.