The Onion does a really good series called "Onion Talks" that satirizes the vapidness of TED talks. They also capture the audiences' "inspired" reactions pretty well.
This is great. I cracked up at this, and this particular one is also likely to be the only Onion content that is not only age-appropriate for my toddler but also educational.
http://www.youtube.com/watch?v=tom6_ceTu9s