In 1927, when Nikola Tesla was asked by a visitor about a string of controversies over some radio patents, he famously remarked "Let the future tell the truth and evaluate each one according to his work and accomplishments. The present is theirs; the future, for which I really worked, is mine." Though he may have been commercially bested by Edison, he's become a cult hero among modern inventors, engineers, DIYers and steam-punk aficionados.
His legacy is alive and well on the internet. Nerd Youtuber Smarter Every Day has turned one of his famous inventions, the Tesla coil, into a handheld gun that blasts out a maze of lightning, Ghostbusters-style.
Tesla's design of the alternating current (AC) electrical supply system and the AC power generators at Niagara Falls are arguably his most famous contributions to society, but the Tesla coil remains one of his coolest, and most beloved by Tesla fans. It's a transformer circuit that pumps out AC electricity in high voltages, spider webbing through the air like lightning. It's resonant, so you can make trippy music and mesmerizing light shows at the same time. And when it's handheld, well, you can point the lightning at stuff. It even comes complete with a water cooled pack. Watch them blast this thing in a driveway and lose yourself in mechanized, electronic joy.