Sometimes I imagine what it would be like to meet the ponies. I usually go with the scenario that it would be awesome and I would get to fly on one of them.
I also like to ponify things in my mind. I take another fictional universe and imagine how it would translate if they were all ponies. If you see a lot of people everyday then you could imagine what they would look like as a pony.
Then I also imagine what I'd do with superpowers. From if I could fly to if I had ultimate control over everyone. You can think of a lot of fun things you could do, but also think about some of the serious implications of such power.
But my favorite game is playing Hollywood producer. I think of how I would remake movies or turn something into a movie. I'm sure anyone playing this way will yield results on par with or exceeding some actual Hollywood projects. And what if you had ultimate power over it all? How would people react if every movie in the year 2018 was a musical?