Prometheus - This 8-Bit Life
This has got to be one of the coolest things I’ve ever seen. The guy in the video’s name is Everett and he has built a pretty sweet device. It features a fuel reservoir mounted behind the elbow, an arc generator for getting the flame started and a servo controlled flow valve to, you guessed it, control the flow of fuel. He has this rigged so that a microcontroller gauges the angle of his wrist. When he lifts his hand up high enough the arc generator kicks on and the valves starts letting fuel flow, this increases as he brings his wrist up.
This is too damn cool.