Another link for the 9/11 conspiracy crowd, Inside Job - Unmasking the 9/11 Conspiracies by Jim Marrs.

I've heard this man in interviews; he's very, very interesting.

"There is also the fact that NORAD-Northeast was conducting war game exercises that morning, a fact that has been very little talked about and certainly not reported to the general public. What's also not been reported, according to the information that I have, at least one of the scenarios they were considering in their war game exercises concerned hijacked aircraft being crashed into buildings. Now, this could explain the lack of response when the air traffic controllers began to report that four planes were off course..."
- Jim Marrs, Author, Inside Job