Black Tourmaline is a highly protective stone against negative energy, I wouldn't use anything else. Also provides spiritual grounding essential for spiritual workers and beginners alike, don't be without one. Assists the 1st (Base/Root) Chakra.
This discusses marine power generation techiniques including wave and tidal power. Many areas of the world expereince consistant and powerful ocean currents that can be used to harness renewable, clean energy!