Using a few household materials like a galvanized nail and pennies it is easy to get electricity out of water, enough to power an LED light. This is a good experiment for kids to try out and adults too and helps teach how to wire in series.
It is also a cool project and provides knowledge that can be applied outside of the experiment. It works from the water acting as an electrolyte for the two metals. Copper is electronegative and the zinc is electropositive. Which creates electricity as one metal loses electrons and the other gains electrons.