This is a list of situations, projects or initiatives in which there could be an “astronomical” (huge) reduction in the amount of suffering compared to what currently exists or is expected. Many of these situations (but not necessarily all of them) involve a high risk in the sense that they are difficult projects whose probability of success is very low. In some cases, this may happen because they are projects that assume as certain some hypotheses for which there is little evidence, so we can consider them unlikely, although not impossible.
I insist that the only criterion to appear on this list is that the project or idea supposes an astronomical reduction of the suffering that we believe exists or will exist. The list can include both remote possibilities and speculative approaches as well as conventional and highly probable scenarios.