Those CueCat scanners were a great way to scan used textbooks when I was selling them in college. They just magically spit out a text string followed by a <CR> when scanning a barcode. They were going for dirt cheap on eBay for a number of years.
In college, on finals week I'd get $100-200 cash and go to the bookstore. I'd hear they were buying back certain popular textbooks for next to nothing. I'd offer the seller $10 cash right there on the spot. "Sell to them or sell to me, it's the same price. Here's a $10 bill."
After getting a stack of those (or when profs were cleaning out their bookshelves), I'd lug them home, scan with my CueCat and sell them for a substantial markup on half.com (RIP).
One semester I found a stack of books outside faculty offices labeled "free" - sold those for $500 that weekend.
In college, on finals week I'd get $100-200 cash and go to the bookstore. I'd hear they were buying back certain popular textbooks for next to nothing. I'd offer the seller $10 cash right there on the spot. "Sell to them or sell to me, it's the same price. Here's a $10 bill." After getting a stack of those (or when profs were cleaning out their bookshelves), I'd lug them home, scan with my CueCat and sell them for a substantial markup on half.com (RIP). One semester I found a stack of books outside faculty offices labeled "free" - sold those for $500 that weekend.