There is a tremendous amount of power all around us just waiting to be harvested. All particles that moves has energy that can be collected. The kenetic energy of one particle can be calculated as E=mv2/2, where m is particle mass, v is its speed. The effect is observable using a powerful microscope. Place a tiny particle (0.001 mm) in a liquid (such as water) The particle is then randomly pushed around by the water molecules. This is called Brownian motion. The problem is that all the molecules fly in random directions, but it might be done with a rotor device like this:
This Brownian motor might not be sensitive to the particles direction, but it needs to bee small, otherwise the particles collide with each other instead, thus not adding to the momentum of the device.
This is a thought experiment to somehow break the second law of theromdynamics, wich I personaly think is flawed, specially when the system is small and quantum effects come into play. The famous Brownian Rachet motor needs more food for thought. For example: what happens when a vacuum is created and only one molecule is left to hit the rachet? It will hit the springs, yes, and the spring will bend, but the rotor will not move backwards because the only molecule left is busy hitting the spring. It will hit the rotor and it will only move forward because of the springs.