Some crazy Swedish dudes have equipped their tricopter with 100-packs of fireworks and gone to hunt some hydrogen-filled balloons. As an added touch, they created a “defense sentry” that automatically launches rockets when it detects the tricopter. The rockets’ fuses are lit with match-heads ignited by a 12-ohm, 1/4W resistor with 12V going through it. [Via Adafruit]