Reaching the general public


I recently discovered that in my home town (Norwich, England) there is currently running a series of "Café Conversations" in which some faculty members of the university that I work at are giving talks/hosting discussions on various topics. The meetings take place in a café that I know, which has room for about 20 people, and are open to the general public. Titles of some of the meetings already arranged are "What is infinity?", "Increasing happiness, decreasing consumption", "Bioplastics: wasteproduct or gold mine?", one on the nature of boredom (really about how old, retired people find things to do), and several on environmental topics. I have not been to any of them -- in fact, only the first of them has happened so far.

The obvious thing for me to do is to volunteer something on rationality, but quite apart from whether I would be able to do that at all (not being the friendly and outgoing, charismatic sort suitable for leading such a meeting), a problem that I foresee is this: these meetings are intended for the general public. This is nothing like a LessWrong meetup, or a Singularity conference, or delivering a lecture which, while nominally open to the general public is not actually intended for them.

Has anyone here had experience of communicating about rationality, one-to-one or one-to-a-small-roomful, with the general public? How do you approach the matter, and how far can you expect to get?

Norfolk, by the way, has given the world the expression "Normal for Norfolk". Go on, Google it.