I thought I'd share this link with y'all:
http://edcforums.com/index.php?topic=17721.0
It's the story of a fellow EDCF'er who was approached by an unknown
(and apparently "harmless" individual). The post does a great job at
describing how we don't pay attention to our intuition. It also
describes typecasting and a few other neat little things that may come
up when a stranger approaches with dubious intentions.
I thought it was a good read,