come on now you can't tell us half a story - we need to know the joke/reasoning behind this!
It started with weekly discussions on "Which [subject] Are You" kind of thing, as in which Buffy character are you, which Car are you, who would play you in a movie, which Rocky Horror character are you, etc etc.
Same as the online quizzes, except that everyone else figures out what they think your answer is. The fun is in explaining how they came to their conclusions - These are engineers, so it's often quite a scathing character analysis!
It got around to cartoons and heroes and stuff, but for an added twist you let everyone have your phone and they set the ringtone for whichever character they figure you are. You don't get the answer until someone phones you!
I'm "quite heavy-handed and headstrong, like Conan The Barbarian" (in the most negative sense possible, naturally) as well as doing the occasional film impression/quote and He-Man was supposedly inspired by the Arnie film... and because people have told me many times *not* to tighten screws or taps, tie knots, set fragile things down or otherwise do something "with the Power of Grayskull".