I carted a couple large boxes of books to Half Price Books yesterday. If you've never done this, they have a pretty organized system for processing incoming books. Books are stacked and their barcodes scanned (or ISBN numbers entered) and sorted into stuff for which they're paying you and stuff which they'll be glad to take off your hands if you don't want to cart it home.
You can tell if they stumble on a real find because they'll hesitate, maybe wipe it down, and double-take at the monitor in front of them. When I saw the clerk do that over a yellow-jacketed book in the stack I brought in yesterday, I figured I'd better google it up and see what I found. I'm glad I did, because it appears that Dougal Dixon's Man After Man is bringing rather more than the $2.99 I gave for it all those years ago.
Anyway, I decided not to sell that one to Half Price Books and threw it on eBay instead.
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