I'll post the link again...so maybe someone will read it this time.
http://www.cassiopaea.org/cass/boeing.htm
It'll help answer questions (in multiple ways and with multiple answers) such as: "Why would our own government do this?" I strongly urge everyone to read the whole article. Then I think we will all be suited to make intelligent discussion.
Edit: Not to say I think the gov't would do this, I just think that alot of the questions that fly around to try and at least debunk the pentagon crash are very well answered in this article.