My buddy Rob built a Tesla Coil at Hackerbot Labs and he did an awesome write up of the process. My favorite part is his warning:
Of course, fluorescent and neon bulbs will glow in the presence of a high voltage field, even without being directly struck by a streamer. One completely unsafe and idiotic thing you shouldn’t do is to ground one end of a fluorescent tube and hold the other end close to the top load. It will light up twice as bright, and you will have several hundred thousand volts flowing through your hands.
What if the ground wire comes loose? Or if your shoes aren’t really all that insulating? Or if a streamer strikes a wire carrying mains voltage, creating a low resistance path between the grid power and ground through you? That could be incredibly bad for you and your next of kin, which is why you should never, ever do this. No matter how cool it looks. – Link