| Anomalies in physics. Inadequately studied phenomena that may contradict or demand the extension of existing theories. |
| Machines suggested by their inventors to extract energy from sources unknown or previously unexploited . |
| Water & Plasma phenomena that reports anomalous energy extraction from water, ionized water or other plasma discharges. |
| Gravitational experiments and anomalies, e.g. relating gravitation and inertia to electromagnetic phenomena. |
Since the free energy area covers the spectrum from more serious research to less serious, any map of the area will reflect this fact. It must be so, as the only way to find out what may be fruitful research and what may not, is to dive into the information and research, trying to create a scientifically honest view. And perhaps then, it is possible to say what is more promising and what is less.