I've seen so many bad slides-based presentations in my life (who hasn't?) that it took me about 14 seconds to order The Cognitive Style of Powerpoint after seeing Aaron Swartz's cool remix.

Tufte's books are part of my "desert island" book collection: If like me you like graphics, you should read at least Envisioning Information which is presented as a book that celebrates escapes from the flatlands of both paper and computer screen. Sounds like marketing but I find it very true in this case.