The astronauts spend time learning how to evacuate pad 39A if an emergency arises, including procedures to operate the slide-wire baskets that would quickly whisk the crew from the launch tower to a bunker west of the pad.
Source: NASA TV (9 min 20 sec MPEG-4 (H.264) file)
Download this clip to your hardrive.
(Windows users right-click this link. Mac users control-click this link)