Geo-Reactors and Rogue Nukes (Score 1)

Although this experiment alone may not shed much light on the geo-reactor theory, there are other proposals for neutrino experiments that may. For example, http://arxiv.org/abs/hep-ex/0609041 describes a proposal for a deep sea neutrino observatory which could be used to measure thorium and uranium concentrations in the core and mantle. It could also be used to test the geo-reactor theory:

The second goal is a definitive search for a hypothetical nuclear reactor at Earth's core. This theory (Herndon 1996; Hollenbach and Herndon 2001) has not met wide acceptance by the geological community, who have generally preferred the idea that much of the U/Th rose from the molten, early inner Earth as slag, rather than sank to the core as elemental metal. Yet, many geologists say that there really is no evidence against the hypothesis since the conditions at Earth's formation are little known. Moreover, there are peculiarities in the isotopic content of Earth, and most particularly the observed high ratio of 3He/4He coming out of oceanic volcanic hot spots (such as Hawaii and Iceland), which a natural reactor could explain (3He would come from tritium decay, made abundantly in reactors).

Slightly off the topic from geo-neutrinos, the same type of experiment could in principle be used to detect "rogue nuclear activity." Details available below. http://arxiv.org/abs/hep-ph/0607095