On io9 a couple days ago:
http://io9.com/whats-the-greatest-scientific-visualization-ever-1645660118/all
Links to some of my favorites:
“The known Universe (AMNH):”
https://www.youtube.com/watch?v=17jymDn0W6U
“The Cosmic Calendar (National Geographic)”:
http://video.nationalgeographic.com/tv/cosmos-a-spacetime-odyssey/the-cosmic-calendar
“Comparison of Star Sizes”:
https://www.youtube.com/watch?v=HEheh1BH34Q
“Scales of the Universe (2)”:
https://www.youtube.com/watch?v=uaGEjrADGPA
And of course, the classic, “Powers of Ten”:
https://www.youtube.com/watch?v=0fKBhvDjuy0