Nikola Tesla is like the photo negative of Thomas Edison. Edison made Direct Current (DC), Tesla made Alternating Current (AC). Edison became grotesquely rich, Tesla died poor. Edison got tons of stuff named after him, including corporations and high schools. All Tesla got was a crappy rock band from Sacramento.
Though it wasn't all sour grapes for Tesla--while Edison invented some pretty common place items like light bulbs and record players, Tesla excelled in awesome invention like robots, wireless electricity and death rays. He predicted the Internet 80 years before its existence. Also, he was played by David Bowie in a movie.
"Immediately, I rule harder than any scientist ever."
One thing Edison and Tesla did have in common was batshit lunacy. In Tesla's case, it was a pocket-sized earthquake generator. In 1898, Tesla conducted an experiment in mechanical resonance in his New York lab, which basically measures the tendency of something to absorb more energy from a vibration if said vibration matches its own natural frequency. In other words, everything has its own musical pitch that, if matched, will break the object, not unlike opera singers breaking crystal glasses with just their voices. Except in this case Tesla's crystal glasses were buildings.
Allegedly while testing his electro-mechanical oscillator (or earthquake machine), many buildings began to shake. Once the very building he stood in began to tremble, Tesla took a sledgehammer to the device, destroying it and likely saving everyone in the city.
"Shit, I've gotta break this fucking thing."