This video from Arecibo observatory has been doing the rounds on the interwebs. It shows the increasing number of known asteroids in the Solar System over the period 1980 to 2010. It gets very pretty around the 2:00 mark, which roughly coincides with the year 2000 (see the time ticker in the lower left corner).
30 Years of Asteroids
August 28, 2010 By




That is really cool.
Thanks Sarah