No, it's just automated pricing based on it being rare. You set a high price, other pricing bots come in and undercut it - unless the book is sufficiently rare or obscure, in which case the high price remains.
Funnily enough, my book is a good example of this. There's three copies on Amazon, priced within 1 cent of each other: http://www.amazon.com/gp/offer-listing/1898275351/ref=dp_olp... It was one of the elss well-selling ones in the series so it's become 'rare' by virtue of its own obscurity, rather than inherent merit of its own :-)
Note to self: set up own pricing bot to bid rare books down to cheap rates and then snap them up. Finally that copy of the Dune Encyclopedia will be mine!
EDIT: Apparently it can be had for only £15 now. How depressing.
Funnily enough, my book is a good example of this. There's three copies on Amazon, priced within 1 cent of each other: http://www.amazon.com/gp/offer-listing/1898275351/ref=dp_olp... It was one of the elss well-selling ones in the series so it's become 'rare' by virtue of its own obscurity, rather than inherent merit of its own :-)