The conditions we discuss are cluster headaches (similar to OPIS), trigeminal neuralgia, and complex regionary pain syndrome. We want to emphasize that we are not experts on either of the three but their victims consistently describe extreme pain, unlike anything they have experienced before. The reason why we estimate that their treatment might be cost-effective comes partly from the intensity of suffering that could be solved and mostly from its neglectedness. To our knowledge, there are none or very few people who seriously work on them and we, therefore, thought that even a small group of researchers could already cure a lot of suffering by developing a better understanding. Due to this uncertainty, though, we find it hard to compare with other pain-related interventions such as access to pain medication in developing countries.