I think that in many ways, physics today is in a similar place to where it was before relativity and QM; it's almost entirely explained, which just a few nagging anomalies around the edges. Today we have QM and relativity, which contradict each other but are very complete, and just a couple nagging issues of matter vs. antimatter and how gravity, inertia, time, and subatomic particles interact. Back then they had a couple issues with the speed of light and a couple other minor details, and famous physicists were quoted publicly as saying that a grand theory of everything was just around the corner. And then along came Michelson and Morley and Einstein and Planck and Heisenberg and blew our understanding of the universe wide open.<p>Sadly, since we've explored domains with sane timescales and mass / energy levels pretty thoroughly, it's unlikely that new physics will result in anti-gravity hovercars or vacuum energy devices or starships or time machines any time soon. But it might make something we haven't thought of yet, like understanding of time dialation and the speed of light gave us GPS!