that anorexia thing is ingenius... did your friend point out at the end that it didnt represent anything, or did they just let people wonder?
i did my first presentation on rumors, the basic concept was what is a rumor, how do they get started, what makes people believe false ones, how do you spread one and how do you stop one from being spread? there's a lot of problems of knowledge associated to this actually, and what makes it particularly fun is to use a case study of some people pranking someone else (get an old chatlog, change the names to protect the innocent and guilty). i got a 17 on it.
but i have no idea what to do for my next one... i tend to go for the social issues type presentations, any ideas anyone?