Excellent Introduction to Gravity and LIGO

This video, Catching the Waves with LIGO (Realplayer required) is an easy introduction to gravity and the LIGO project. The video is a recording of a speech given by Dr. Barish, head of the LIGO project. Extra bonus: hear a radio pulsar!

The source page is here. You can choose versions for 56K modem, DSL/cable, or broadband.