This idea came out of a project I put together way back in college--a shocking (gift-wrapped) present. The present would shock you when you would move it if you were touching any two opposite sides. I'd get it out every year at Christmas :) It contained an ignition coil from an old junk car, a 6-volt lantern battery, and a mercury switch to close the circuit when the person shook or tilted the present. I got bored with it and thought I could convert it into a shocking mouse instead--here are the details of the conversion.
For more how-to's visit my blog: John Fixes Stuff
Step 1: Schematic Overview
The basics are that the coil steps the battery's voltage way up but because we are using a small 6 V battery the current is low. The mercury (tilt) switch activates the circuit and you get a shock.
BTW: Be careful with this thing. I can't take any responsibility with what you do with it. If you aren't comfortable with electronics and electricity then pass on it. Do not use this on someone with heart trouble or a pace maker--that would not be funny.
Step 2: Choose a mouse.
Step 3: Disassemble the mouse.
Step 4: Prep the insides of the mouse for the project.
I then cut the circuit board in half width-wise to make room for the mercury tilt switch. I kept the plastic lens so that the mouse looks totally real from the outside. I clipped out almost all of the plastic tabs from the top and bottom of the mouse to make room for the surprise we're going to put inside!
Step 5: Drill holes for the contact wires.
We are going to run a thin wire on each side of the mouse, in the seam, right where your hand grips. The back of the seam actually belongs to the top half of the mouse case. This is important because we are going to drill holes (on each side) in that lip that overlaps inside the seam. One hole for where the bare wire comes out of the case and another where it will go back in.
I used a 1/16" Dremel bit (just slightly bigger than the strand of wire I'm working with). The bit I chose was actually smaller than any of the Dremel chucks I own so I had to use my cordless drill.
Follow the series of pictures (and the details included on each pictures) for the steps on where and how to drill the holes.
Step 6: Prepare the contact wires (the wires that do the shocking).
The other contact wire will be done the same way but it isn't one of the wires connected directly to the new mouse cable (refer to the diagrams). You can use one strand out of a different section of cable if you want. In my case I had a piece of wire connected to the mercury switch already that I used.
Step 7: Run the contact wires.
Run the red wire (based on my diagram) out the first hole (from the inside). I hot glued it in place before I went any further. Shape the wire so it runs tight along the seam and then back in the other hole.
The second contact wire is the one that connects to one side of the mercury switch (refer to the diagrams for which side). I already had some multi-stranded wire soldered to the switch so I won't be using the same kind of cable that we just used so I picked one of the individual strands of wire and then cut the rest of them off.
Insert the wire in the first hole and then glue the wire in place (see picture). Shape the wire just like you did the first one and run it back in the second hold and bend it to hold it in place.
Step 8: Secure the mercury switch inside the mouse and make the proper connections.
You'll have to play around with how you are going orient your mercury switch based on the space constraint but the more horizontal the better (verses orienting it top to bottom) because people tend to move the mouse back and forth (left/right), versus up and down, when they grab a mouse and move it (to wake the computer up from the screen saver). You want to make sure the glass end of the switch is lower than the wire end because you want it off in the natural/flat position. You'll also want to look at how the contact points are oriented inside the glass bubble because you want them pointing down. See the pictures for the way I mounted mine (this picture is of the final project actually, because I relocated the switch after the first run).
Connect the wires as shown in the diagram and arrange them so there is clearance to put the mouse back together. I used wire nuts to connect the wires because they are less work than soldering and heat-shrink tubing but they take up a lot more space and I had to hot glue them in place to keep them from getting in the way when I was closing up the case.
Step 9: Connect the battery and ignition coil.
I added a switch between the negative of the battery and the black wire in order to be able to shut off the mouse so I don't shock myself (anymore than I already have in testing the thing) and so I can transport it without running down the battery. I placed everything in a box and added some cardboard to fill in the gaps so the parts don't roll around. You definitely don't want to try taking this with you on a flight because you'd make the evening news!
Now it's time to test out the shocking mouse--ON YOURSELF. I always test it before deploying it and that way I know it's working and I've experienced the deal myself that I'm going to subject someone else to.
This is nothing like a stun gun but they always make cops get stunned before they let them use it on someone else.