There were a lot of variations ever since someone (name escapes me, but I think they had a gandalf avatar?) first posted a "what superpower did you random" thread once upon a time. I remember the one you're talking about, and I remember my own variation was to hit random twice and try to come up with some explanation for how how started with the weaker/less versatile power and ended up with the stronger one. That one wasn't quite as popular.Wasn't there an old thread which had this, but you were supposed to explain how a fight between you and the poster above you went?
That was fun.