Whats the rarest/coolest/most unusual book you own?

[Aimless Gallivanter]

Titles pretty self-explanatory! Tell us about a cool book you own!

Maybe one signed by the author? A special edition print you bought recently from B&N? Perhaps a very old book you've never read but wow isn't the binding neat? A peculiar book you found in a dark forgotten corner of a dusty used bookstore? 

[Jetthebinturong]

I have a proof copy of Odysseus in the Serpent Maze by Jane Yolen and Robert J. Harris. I should get the rest of that series.
I also have a signed copy of The Emerald Atlas by John Stephens.
And I have American editions of the first three Heroes of Olympus books. (The English covers are really bad for basically all Rick Riordan's books, but especially HoO.)

[Gonff the Mousethief]

I have an of Mossflower signed by Brian Jacques. Besides that, I don't really have anything except a very old collectors edition of Sherlock Holmes.

[Vilu Daskar]

I've got a Mossflower collectors edition and a cool looking Sherlock Holmes book with maps.

[BadgerLordFiredrake]

Signed copy of The Legend of Luke.

[Rusvul]

   I own an elaborate leather-bound copy of On the Origin of Species that I bought when I was 8. What I didn't realize was how verbosely it was written, I still can't read it properly due to all of the archaic and technical words in it. But hey, it looks like a spellbook, so... Worth?

[Dotti Dillworthy]

Old 1950's edition of A Connecticut Yankee in King Arthur's Court by Mark Twain. A keepsake from my grandma.

[Aimless Gallivanter]

I have an old copy of that too, Dotti! I dont remeber how old it is though. I'll have to take a look later. My dad gave it to me for Christmas a couple years ago.

[Wylder Treejumper]

I have an excellent copy of an old book called Johnny Reb and Billy Yank: How They Fought and Made Up. It was printed in 1959, and is my favorite history book I have ever read. Its narrative depiction of the Civil War is really the reason I became a history buff, reading that from an early age.

I also have a book on the politics of World War II, by Winston Churchill, printed in 1950, but it's super boring.

[Banya]

I have a signed copy of Loamhedge and the 1959 revisions of the first eight Nancy Drew volumes.