I think this was a blog a while ago, but whatever.
Basically what you do is make a random question about MLP or anything else and then the next person to post must answer that question. It doesn't have to be right.
Person 1: My favorite pony?
Person 2: Applejack. My favourite episode?
Person 3: Suited for Success. The name of Pinkie's sister?
Person 4: Maud. My favourite video game?
And so on. I'll start with a question about myself or MLP and the first person to answer in the comments gets to answer the question. That person then posts a question and the next person posts an answer and question. And so on and so on.
My favourite pony?