I just saw this video, made by a couple whose apartment offered an incredible view of the North Tower. There are several interesting things about it that I caught on an initial viewing: witness describes "military plane" hitting South Tower (no shot of it, though), another witness describes plane as "really big," intense shots of the pyroclastic flows, shot of the "spire" component of the structure (left after collapse almost complete) seeming to collapse straight down rather than topple.

http://www.revver.com/view.php?id=59686