I first started building the coil over ten years ago, but never got around to finishing it. My new coil is not exactly same as the one I first started building, but I did use the components from the original one.
The coil is around 35cm high, uses a 4kV neon sign transformer as its power supply, and currently produces sparks about 15 to 20cm long.
Here is a video of the coil in action: