We’ve covered a few tesla coils, but somehow we never hit this classic – making your own jacobs ladder. The spark climbing the increasing gap between a pair of electrodes is easy enough to create – just get a high voltage transformer (like a neon sign transformer), make a set of insulated electrodes and wire things up.

Now that I’ve mentioned a couple of HV sources, I can point to this set of awesome high voltage photos from the same guy that put together the portable tesla coil.