When Barry travels back in time to save his mother in The Flash, he'll get stuck in the Speed Force and meet the Barry Allen of Earth-Prime, giving us the sequence we saw in Crisis On Infinite Earths again, giving us more to that sequence and full context for it.
Thoughts? Is it possible? Impossible? Stupid? Let me know and check out my other Flash theories (as I'm sure to develop more as we get closer to the release date)!