Couple years ago now I found a copy of Wendy Carlos' "By Request" at Half Price Books for $8.49. Generally HPB checks the interwebs before pricing stuff, but not this time -- all of Wendy's catalog has been out of print since 2009 and is priced accordingly. This particular CD goes for close to $100 everywhere you see it.
So I listed mine on Amazon for, what was at the time, slightly less than the others, or $78.
Somebody bought it today.
It still has the HPB price sticker on it. After a moment's reflection, I stuck $70 cash inside the case. I know the CD's going to somebody who REALLY wants it, but my good fortune should be shared.