And here I thought it was involuntary.

It's voluntary - I've never done it in my life, not once. I'll just explode when I'm 50.

Now if lighting one up were banned, that might make sense.

That process is a valuable tool in PA Crew boot camp training (those who don't care for my sense of humor should not watch this)

http://www.metacafe.com/watch/404605/fart_lighting/