I guess I am WIERD here! I actually tested some circuits by seeing if I would get shocked. I have been shocked by 120v household current, about 3 times, ONCE on acident because I slipped on a test. I have been shocked by a much higher voltage, but lower current, on inductors. Anyway, I don't think I have tried to do that since about 10yo. I now have a nice meter to check such things. When I work on house wiring, I flip the appropriate circuitbreaker. With cars, I TRY to ground things properly.
I NEVER did the battery trick. That could have been more dangerous than you would believe. They could concievably have caused a short, sparked and started a fire AND exploded and sprayed acid all over. You were LUCKY!
As for the microwave, there should have been a case against the manufacturer.
But I DID always make sure the circuit was closed EARLY! If you don't complete the circuit created on your hands, for example, and sit on something that is grounded, it can take THAT path, and kill you. The inductors were USUALLY such that it was just inductive kickback. It can feel WORSE than a normal shock, but is far less likely to kill.
Of course, the tesla coil, like you probably saw at the griffith observatory, has a big inductor in it, but you basically feel the generated field. It isn't so direct. His dream was to provide SO MUCH power at such a HIGH frequency that you could basically tap it ANYWHERE. Almost like a remote control in reverse. When you press ON on a radio remote control, it sends LOW POWER EM radiation to cause the local switch on the remote device to turn on. Tesla's dream was to have a device you could turn on that sends HIGH POWER EM radiation to power the remote devices.
Even the "van de Graaff Generator" is somewhat similar to the tesla coil. Of course IT is lower tech and lower power.