For me it would probably have to be Thirteen Steps to Mentalism...so much knowledge and so many applications for it too.
If I was feeling crafty however I would merge several books together in to one hefty tome which would consist of the above book, Kentonism, Modern Coin Magic (still learning me coins) and Magic and Showmanship. But I guess that's cheating really .
Smoke and Mirrors? Never read this of even know what its about,
For me it would be Harry Potter
Magic is real, just look around you, some of the most amazing things have no reason, no explanation but are very real. Quote - Appreciate The Trick For What It Is!
Personaly I'd be torn between the Vernon Biography and the Art of Astonishment.
Treasured possessions.
Art of Astonishment reminds me of a Police Squad! or Airplane movie... every time you see it again, you find something different and more interesting than the previous time.
These are two of my most treasured books, partly because they were given to me by my late father but also because they are so evocative of a magical era long ago.
I'd be torn to pick between them but the Davenport catalogue (from the mid 1950's I think... it's not dated) is a fascinating read. Tricks like "The Rising Floating Match" for one shilling (that's 5p to you young 'uns) or a set of pocket size Chinese Linking Rings for 4/- (20p!). The frightening thing is that I actually remember going into the original Davenports shop on New Oxford Street when they were still selling a lot of this stuff (although I hasten to add that it was a few years after this catalogue was produced! Ahem!!). Around 150 pages of history in this book, for anyone interested I have photographed three of the pages here: http://tinyurl.com/kbfp6
I would have to also say Corindas 13 steps would be my book. But, it is only on volume of good information. The book I learnt the most from as far as quality would be too hard to pinpoint. I would have to say the kenton books, Kentonism, Mind Reading, and Trance This! along with Richard Buschs Peek Performances and Destiny Response all have equally created what I do right now. If I lost any one of them I think it would drastically change what I do.
I'm going to go with Absolute Magic. I'm re-reading it at the moment and, as most of my stuff is now homebrewed, for me it's knowledge of presentation that's important rather than sources of new tricks.