A true first edition, of which I believe only several hundred copies exist, of the first Harry Potter novel has sold at auction for $41,000. You read that right, I did not add an extra zero... Signed by the author as "Joanne Rowling," the book was sold to an anonymous bidder at Christie's auction house. More power to 'em, I guess.
Still, I consider that to be a ludicrous amount to pay for a book that's only 10 years old. I say that from a collector's perspective with an eye cast toward investment potential. Despite the current immense popularity of Harry Potter, it is anyone's guess as to whether these books will stand the test of time. Also consider that this price paid is far in excess of what true cornerstones of the fantasy field command. More than The Hobbit or Lord of the Rings and far more than anything by Jules Verne, H.G. Wells, or H.P. Lovecraft.