Tesla Coil

Tesla coil is actually a transformer invented by Nikola Tesla.

It is a step up transformer which increases the input of 120 volts AC to around 100,000 volts.

The discharge is usually in the form of electrical arc.
These incredible coils have in the past were known to light up florescent lights which were almost 50 feet away, wirelessly.

The other fact is that there is a direct conversion of electricity to light which does not need the electrodes, unlike the normal bulbs.
What it means is that, the florescent lights which have already burnt out can also produce light.