willosof is building a gatling golf gun for his own unknown :) purposes but apart this, the construction is pretty solid and as maker claims it can shoot golf balls up to 200+ meters.
The firing power is provided from a mixture of propane and air controlled through solenoids and ignited from an 23000 volts xenon-hid ballast!
You can check the progress and watch more videos of the construction here.
imsmoother developed an induction unit that can levitate and melt solid copper and steel. The unit uses microprocessor controlled resonance locking to find and maintain the proper frequency for the induction heating. The unit is capable of handling 10kw of power. The demonstration uses 8-10kw. Levitation of aluminum, which is less dense, requires only 1-1.5kw of power.
It is impressive to see it in action but if you want more info here is the place to look.
Hans J√łrgen Grimstad is making a clock with some nixie tubes and a dekatron and houses it in a beautiful case. The result is really good and that "nostalgia" feeling surrounds it, inside though arduino and xbee modules keeping the clock running.
Details can be found here but not all in English.
Guys at EasternVoltageResearch made a tesla coil kit that was specifically designed to reproduce high quality audio through plasma modulation. In otherwords, the high voltage arcs from the Tesla coil are modulated so that they create audio sou...
rmcybernetics build a 1kW Synchronous Rotary Spark Gap tesla coil that is capable to produce arcs up to 74cm! The whole build is made with quality in mind and of course the result is equivalent. You can find very detailed step by step info and schematics at rmcybernetics page.
This Tesla Coil is playing the Monkey Island theme. The RF is generated with a Class-E MOSFET stage with controllable Frequency. The sound is modulated on the gate signal of the MOSFET via PWM. The sound is then emitted by the arc itself. The sound is very clear.