Monty Python's Flying Circus
Season 1 - Episode 01 - Whither Canada?
Recorded 07-06-69, Aired 05-10-69
Contains the skit "The Funniest Joke In The World"
http://www.youtube.com/watch?v=8gpjk_MaCGM
Talking openly about peak oil can often be like that, except for the funniness part.