I presented to a hometown group of about 60 folks sitting on hay bales during a cool clear night at the Marys Peak Natural Resources Interpretive Center.
I was amazed and delighted to hold the interest of this nontechnical audience for about 40 minutes, after which they continued with a half-hour of thoughtful questions after the presentation. Here is a Powerpoint presentation targeting a sharp nontechnical audience, intended to explain to the folks in Philomath Oregon just what it is that we do across the street from the Georgia-Pacific mill.

http://www.gene-tools.com/files/Philomath2008.ppt

I learned something: if you explain tough concepts carefully to a lay audience, they’ll get it. Well, perhaps I was just lucky to be presenting to a good crowd in Philomath.