Previous to the atomic bomb, science fiction authors were trying to puzzle out how recent developments in nuclear science would effect us. For example, in 1940, Robert A. Heinlein guessed that we might turn uranium into a super weapon and dump radioactive dust on our enemies, making their territory useless (in Solution Unsatisfactory, although I believe he used the idea a couple of times) – I think he can be forgiven for not seeing the a-bomb coming, it was a year before the Manhattan Project had been created.
I believe we’re on our way towards a similar epoch, related to our current energy lust. A combination of personal electronics, and the need to collect and retain greener sources of energy, will push us into a battery\fuel cell revolution.
So – electric cars, sure, but what other opportunities do high powered batteries open up? Independently operating robots? Body-implanted computing? Jetpacks?
I suspect any guesses will appear dusty by the time the future rolls around.