Honestly, I don't really try too hard, or expect, to change anyone's mind. All I can really hope for is to throw out one little nugget of info that will make someone stop and think for a sec, make them say "waitasec, is that true??", and then hope it snowballs from there.
That's what happened to me a few years ago, and I think I've been able to do the same favor for one or two others since then.
