Speculation of Attack Prior to Sept.11,2001
It's quite shocking what people post sometimes. I remember a post to MSNBC message boards last summer, a frustrated person that really wanted to know how much damage a big jet crashing into a highrise would make. It was too blunt for me and I didn't respond to it - I thought it was a little strange. Obviously there is no hope of tracking down that post now. But here is one from a couple years back:
Google Groups thread