When I was a child I used to amuse myself by imagining how things would look if light moved at a few meters per second. I thought it would be cool if you could walk into a dark room, turn on the light and watch as the light spread throughout the scene. Wielding a flashlight would be interesting – you could easily make curved beams.
Now these guys have built a camera fast enough to show the same effect:
Of course, they do cheat a bit by only taking a 1 dimensional slice at a time and relying on the fact that they can repeatably fire identical pulses of light to make their images. Still this is exactly what I imagined it would be like.
Now someone needs to build the high wattage laser targeting system capable of taking out houseflies without blinding humans that I invented when I was 9.