Totally off A10 topic, interesting and detailed technical presentations of the investigation. Makes me try to remember to take care of details.
NASA - The Challenger Disaster and Investigation
http://www.youtube.com/watch?v=Fwb6ZQImCjA&NR=1do a search for part 3,4 & 5.
Challenger: The Untold Story
http://www.youtube.com/watch?v=EQmmnlsj5F4