I've made a robot that screams[0]. That is, just outputs a random string of "AAAAaaa" when its name is mentioned or when somebody else screams (four or more A's).

What is surprising is how basically 15 lines of python implementing these rules, invokes a very real emotional response in a lot of people :-)

I named it "Wilhelm".

[0] inspired by this comic http://gunshowcomic.com/513