Alternative universes

At several points in history, a simple wave of a hand or a different word could've changed the entire outcome of a situation and lead to a drastically changed future.

What were to be, if, for example, the Kyuubi was not sealed in Naruto but in somebody else, or not at all? What if Sasuke had decided to take Sakura with him when he left Konoha? What would have happened if Naruto had been captured by Akatsuki long ago?

Many questions, but only reversing the flow of time and then hitting play again can show....