I've made several static electricity generators before and they've always been a project that draws a lot of interest. They're quite fun to play with and are capable of some really cool tricks. Besides simply zapping your friends (and yourself) they can make dust particles and sand behave wildly as they are attracted to the static charge. They can also attract streams of water, charge pieces of paper so they can be stuck to the wall, and used for a wide variety of magic tricks. Here is a gfy of a static generator in action: https://gfycat.com/YawningRegularHarlequinbug

The above video demonstrates the process for building this project and a text version will follow in the steps below. This is my 3rd version of a static electricity generator and the least expensive, but also the weakest. My last version which can be seen here provides a much stronger charge, but as a result can be painful to use as the shock is quite intense. The version presented in this instructable provides a charge just about the same strength as a regular static charge you probably remember from running around on carpet in your pajamas.

The USB Ionizer which is the primary component of this project can be found here (this is an affiliate link, admins let me know if this breaks any rules and I'll be happy to remove it): http://ebay.to/1Tc8IIZ

Parts:

USB Ionizer
Insulated Wire
Heat Shrink Tube
Hot Glue
Flux Core Solder & Soldering Iron
1.5v Button Cell Batteries
Electrical Tape

Step 1: Dissembling the Ionizer

These ionizers come apart hilariously easily. If you were to actually use them as intended I imagine the case would crack open on you within a week. A pair of needle nose pliers easily splits it open to let us get a look at the circuit board. As a side note, I wouldn't recommend actually plugging one of these into a USB port on a computer. High voltage and PC components really shouldn't mix.

Looking at the last two images I have of the board you can see I've marked it into two sections. The first half nearest the USB port is a circuit that converts the DC current from a USB power supply into AC, which is then fed through a tiny transformer into the second half of the board. The second half contains a chain of 4 consecutive voltage multipliers which require AC to function, but at the end feed high voltage DC into the white output wire.

The circuit is already exactly as needed to output a static charge, but it'll need to be modified to run on batteries to suit my purposes.

Step 2: Adding Input & Output Wires

To change how this board will be powered the first step is to remove the USB terminal. Two tabs on the side are pried off which then only leaves the four connecting pins preventing it from coming free. Touching a soldering iron across all four at the same time allows it to drop away.

On the opposite side of the board there are markings to indicate which terminal is the positive input and which is the ground, marked V+ and GND respectively. I soldered a wire into each of these terminals which will be the connections for my batteries.

In the last image you can see I'm working on the opposite side of the board, where I've desoldered the short white output wire and am reattaching a new, much longer one.

Step 3: Insulating the Circuitry

I'll need to protect this board from the high voltage it will be generating or it may very well fry itself. Before covering it up I first hot glue the wires to the back side so there's more holding them than a tiny dot of solder. I then slide a section of heat shrink tube over the whole unit and use a gentle flame to bring it down to a form fit. The ends don't completely seal closed so I fill that space in with hot glue. These ionizers come with an indicator light to let you know when they're on, so I did shave off a bit of the heat shrink to reveal the LED.

Step 4: Powering the Generator

The USB power supply that these devices were made to run on provides 5 volts of DC. It's a bit tough to find a battery that supplies 5 volts, but usually electronics can operate on a small margin off from their intended voltage. Three 1.5 volt button cell batteries can be combined to provide 4.5 volts which is close enough.

To attach them, I strip a short section in the middle of the ground wire (still leaving a long insulated tail attached) and fold it over to make a protrusion that will be used to press against the negative terminal of the batteries. I hit the exposed fold of wire with a bit of solder to keep it together.

The batteries are then stacked between the two input wires, with the positive input contacting the closest positive battery terminal, and the ground contacting the opposite negative terminal. Some electrical tape holds the stack of batteries together and keeps the wires pressing against the terminals.

If desired, a switch could be spliced into the positive input wire to turn this device on and off, but I've opted for it to be on by default. To turn it off, I insert a small shim of plastic between the batteries to break the connection.

Step 5: Conclusion

The device is now fully functional. To use it to charge your body (or any conductive object), the output wire must be touching your skin, while the long tail end of the ground wire must be in contact with the surface you're standing on. More conductive surfaces will allow the device to work better, as it will more efficiently be able to build a charge differential between yourself and the surroundings.

For my past generators I have made velcro connections to attach the output wire to my body, as well as strap the ground wire to the bottom of my shoe. If you'd like to see how I went about that modification you can check out my last instructable on the subject.

That's it! I hope you enjoyed reading about this project, and be sure to leave my some pictures in the comments if you try it yourself!