I was in Thermodynamics at the time.
I came out of the class to find a friend standing outside in a state, looking like he was about to smash something. He told me what was going on, and my blood went to ice as I had friends and family in that area- in fact, one worked in the WTC. It was days before I could confirm that everyone was okay.

Had I been in power at that point, I would have turned Afghanistan into a large glass ashtray with a lot of incandescent wisps over it, lit by an enormous mushroom cloud.
( The Resident Loon Not a demographic. Do not measure., Thu 11 Sep 2008, 12:39, archived)