Makes me damn proud of my associated with Purdue, actually. The short version is that researchers at Purdue, which is known for having one of the finest engineering schools in the country, have concluded a 2.5 year study on the 9/11 attacks. The focus of the study was to examine the structural failure of the WTC towers with an eye towards designing buildings that could withstand aircraft strikes. The full article on http://CNN.com is here. The researchers also posted a simple computer model of the attack on Youtube, which I've linked to here. I will say, that if you don't like reading the absolutely inane drivel of the 9/11 "Truthers", then don't read the comments on the video.
This excerpt is from the CNN article.
A computer simulation of the September 11, 2001, attack on the World Trade Center, posted on the Web site YouTube by Purdue University researchers, shows how hijacked planes crashed through the twin towers, stripping fireproofing materials from the steel columns and eventually leading to their collapse.
Of course, this won't actually do anything to shut up the "Inside Job" movement, who amongst conspiracy theorists have the remarkable ability to jam their fingers in their ears and not listen to reason.
Unfortunately, as proud as I am of Purdue for releasing this study; I also know it won't do any good with the conspiracy types. Not because I think the study is flawed or anything silly like that, mind you. It's because you can't argue with a conspiracy theorist. Since they're not dealing with reality, any factual evidence can explained away by another government coverup. It must be great to be able to just make stuff up when the evidence stands against you.