Our conventional SETI endeavors have focused on detecting artificial signs with communication techniques that are in everyday use in our present state of technical culture. These include the use of electromagnetic waves, i.e. radio, laser, and visible light communication techniques. What would be the most extreme (on a planetary scale) ways of showing one’s existence over the vast distances and hiding structures (i.e. interstellar clouds, star clusters etc.)? Could ETI use e.g. neutrino transmission, or high energy peaks to overcome the difficulties the conventional techniques have? This paper will review some of the extreme, but feasible channels that could be incorporate into SETI from advanced particle and astrophysics.