PBS did a special show about how the WTC towers fell . . . I thought it was particularly interesting and an excellent documentary . . . I think it was a one hour presentation . . . computer models were created explaining exactly how the towers were constructed, they interviewed lots of people directly involved with the design and building of the towers and so forth . . . there was one really amazing "real" video clip showing a zoomed-in, slow motion analysis of the building as it failed . . . you could literally see how it sort of ripped apart from one side to another in probably just a few seconds and then the pancake effect set in and then "whoosh", it was gone . . . truly phenomenal video . . . anyone else see that?