I've got a colleague who's always checking to see if his books are being sold used online, and what the going rate is. Out of curiosity (and to avoid looking at midterms), I checked out my own Global Perspectives on Medieval English Literature, Language, and Culture.
ABEBooks lists four copies right now -- priced at $28.00, $30.00, $30.50, and $87.98.
Wait ... $87.98? The book is still in print, and sells for $45 from MIP! Someone out there is hoping to get double that? What is it, a gold-plated edition?
But wait -- there's an insult lurking elsewhere in those results. The $28.oo description runs like this: "Hardcover with DJ. Unread, as new."
Unread?! UNREAD?! You couldn't even be bothered to break the binding? So basically, you took one look at this book and said to yourself, "This looks so bad that not only will I never read it, but I'll sell it at half its value in the hope that someone will use it as toilet paper!"
So, to whomever sold my book unread, I say this: Therein were the secrets of the universe. And now you'll never know them. So there.