Loose Change (now released in a second edition) is a video that promotes 9/11 conspiracy theories. Screw Loose Change "Not Freakin’ Again" edition is a response video that pretty thoroughly debunks all of the claims made in Loose Change. It’s almost three hours long, but worth the time to see how vacuous the 9/11 conspiracy theories really are.
This video is in 20 parts on YouTube. If you prefer, it’s available in one piece on Google Video.