Here is some of my favourite pictures that I bumps into when I surf the net.
From: http://digital-photography-school.com/blog/photography-deluxe-25-precious-photographs-from-the-web/
From: http://www.neatorama.com/2007/01/02/13-photographs-that-changed-the-world/
From: http://digital-photography-school.com/blog/41-delicious-flower-photographs/