So you want to test people's stupidity while trying to get their Facebook passwords, this is what you do, and it must be planned. Get a group of kids, like five, and make one of them post something like this: how weird, if you comment your email and then password, your password would show up as stars still O.o... Then get your other four friends to quickly(!!!) comment their email and password as this:
fakemail@gmail.com *********. you have to do this quick enough so that you are the first four to comment, then have a pencil or camera or whatever to be ready to write down any idiots email and password quickly before they erase their comment and feel like dumba**es.. And then quickly login to their Facebook and change their password, and voila, there you have it
P.s make sure to use your actual email and vary the number of stars. Then if anyone fell for it, delete the post