Had a pretty good time selling my old shit a few weeks back- since I was a long-time customer, they bought a bunch of random stuff (some of Johns's early Teen Titans stuff, Winick's Outsiders, etc.), and a few Trades (the out-of-print Flash-Venom one, and Necrosha) for 75 bucks.
And then, of course, they were interested in New Mutants #98, a book once so innocuous that I got it as part of "100 New Mutants issues for $100" last time they did a sale on "multi-pack" books. So for the price of about a dollar (it was missing some books), I sold it for friggin' *$175* in store credit, because of course that movie came out and suddenly this piece of shit book I was keeping in a bag with fifty other ones is now worth a freakin' mint, even though it was graded at like 5.5-6.0. Unbelievable how this works.
Of course, it broke up my "perfect run" on the book, but that shit is easy to replace via Trades or whatever.