A really eye-opening clip from the IMAX movie "Cosmic Voyage"
Travel away to the uttermost reaches, and then in to the tiniest particles. Amazing special effects. Narration by Morgan Freeman.
Update: (11 Jan. 2009) This recently came out on blu-ray. I had it on DVD already but I bought it again on blu-ray. It's that good. The blu-ray version is in 16:9 widescreen. It was about $20 on Amazon when I ordered it.