A simple 3x multiplier powering a linear regulator.just found it interesting.the multiplier itself also serves as a rectifier so the output is DC the regulator smoothens the ripples as pip said in real life the losses from diodes etc are going to be enormous so it probably wont behave as its shown here .this has few limited purposes like in old tv`s to drive the raytube, so its just educational.ive also heard that it could be used to make sparks between gaps by multipliyng the voltage to a point that it breaks the air isolation,but i think a special step up transformer should be designed for this.like a bug zapper actually :D