Storytelling prompt that just came to mind. You live in the Fallout universe, it's October 2077. You just invented a time machine. You know war is coming, so it's time to prevent Jud- Total Atomic Annihilation. What do you do?
(the person who helped you invent it said "invent the transitor earlier" caused something he time traveled to prevent that made YOUR universe, so don't do it)