Looking through my list, none jumps out as a 'life changer': http://davids-book-reviews.blogspot.it/ Although there are several good ones there: * Nathan Barry's Authority: http://blog.liberwriter.com/2013/11/21/nathan-barrys-authori... (http://blog.liberwriter.com/2013/11/21/nathan-barrys-authority/) * Worthless, Impossible and Stupid: http://davids-book-reviews.blogspot.it/2013/09/worthless-imp... (http://davids-book-reviews.blogspot.it/2013/09/worthless-impossible-and-stupid-how.html) - not one for the ages, but I thought his take on entrepreneurship was interesting. * http://davids-book-reviews.blogspot.it/2013/08/pathfinder-jo... (http://davids-book-reviews.blogspot.it/2013/08/pathfinder-john-charles-fremont-and.html) - biography of John Fremont. Interesting guy in an interesting period of American history. * http://davids-book-reviews.blogspot.it/2013/02/innovation-an... (http://davids-book-reviews.blogspot.it/2013/02/innovation-and-entrepreneurship.html) - Innovation and Entrepreneurship by Drucker. Still a very relevant book in a lot of ways.
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