Button batteries are a great power source for electronic projects. The problem is connecting them. This method accomplishes this so simply and cheaply its ridiculous.
Step 1: What You'll Need
You'll need a clothespin, some hook up wire- red and black would be best, to denote negative and positive. And of course, a button battery. I used one that puts out 3 volts as its the perfect voltage for LED's
Step 2: Drilling
Drill a small hole straight through both legs at the end of the clothespin.
Step 3: Wiring
Strip about 2"(50mm) from the end of each piece of wire. Open the clothespin. Push the bare wire through one hole and wrap it all the way around one leg of the pin. Do the same with the other bare wire and leg.
Step 4: Hook It Up
Open the pin and clip the button battery to it so that the + connects with the red and the -- connects with the black. Strip the other ends of each wire and connect to your circuit. Considering you can buy 50 clothespins for a buck, I claim it to be the cheapest battery holder in the world!