I was bored out of my skull and watching some gameshow on afternoon tv. They interrupted that with a newsflash about an airplane crashing into the World Trade Center, went back to the show, then cut out for good a couple minutes later. I spent the remainder of the day watching coverage. At one point, there was some news anchor talking in some NYC highrise office with a view of the towers - or rather, a view of a cloud of dust with a very dimly perceptible outline of the towers in it - and I noticed that the towers seemed to have collapsed a minute or two before they mentioned it.
My dad spent all day working, went to some Green Party social event late at night, and was surprised to find almost nobody there and those who were there huddled before the television.