I previously reviewed the fabulous Presention Zen book by Garr Reynolds.
My favorite aspect of the book was the hundreds of sample slides which illustrate design principles, particularly those illustrating before versus after transformations.
I’ve just discovered a great online resource from Garr Reynolds which contains a representative sample of the book contents.
Sample Slides from Garr Reynolds
Via SlideShare.net, here is a set of 85 sample slides taken from his book or from his presentation library.