well you can build a faraday disc generator for high current but it's a bit of a pain
umm...can get those supercapacitors. like 2 volts but extreme currents.
what else? likely just a step down transformer(rewound Microwave oven transformer with like 2 turns) it would produce extreme currents and is cheap....bit dangerous. would need to be rectified by high current diodes but those are cheap. likely would need two of them, one as a ballast(inductive load) and one as the power supply. otherwise it just burns up.
here lies antinventor2020, he tried