Since you're all posting astrophotography shots, here are some of mine:
Comet Hyakutake in March 1996:
Comet 17P/Holmes, November 2007:
The Space Shuttle a few minutes after undocking from the International Space Station, August 2007:
Lunar eclipse, February 2008:
Conjunction of the planets Neptune and Jupiter, July 2009. When this happened in 1612 and 1613, Galileo observed the planet Neptune centuries before it was officially "discovered":
Total solar eclipse, July 2009:
The moon a few hours before the Kaguya spacecraft crashed into it, October 2009: