My high school recently had an engineering fair, and my friend had built a tesla coil. Its has multiple spark gaps, an RF filter (I think thats what its called), a 120 to 20000v transformer, and toroid top-load, if any of that matters. We/I would entertain ourselves by standing away from the coil and holding a fluorescent tube (by the glass with bare hands, not by the contacts) near the top-load and watching it light up. Even though I was well away from the coil, my forearm muscles would twitch, especially it the coil spark hit the contact on the other side of the tube. Then if anybody touched me, both of us would feel a shock and the same slight twitching (the same kind of twitching you feel from those electric muscle stimulators with the pads you put on sore muscles). We even set up a chain of about 5 people holding hands, and all of us would feel a shock, even though only the first person in the line (aka me) was holding the fluorescent tube near the coil, with my hand on glass, no where within range of the streamers coming from the top-load. Now for my question: is this dangerous? (I know its non-lethal, im talking about my nerves) And what exactly was happening? because it was not an incredibly large coil, and i know that the field of a coil is much larger than the actual streamers. I also read somewhere that insulators dont work the same at incredibly high voltages. I think what I was feeling was the skin effect, and the charge came from the excited electrons in the tube. If my ideas are correct, then wouldn't me holding the tube be just the same as if i had just put my hand near the top-load and let the streamers hit me?