The same fractures that send natural gas streaming out from deep wells also allow geothermal heat to be tapped from practically anywhere on earth. (scientificamerican.com)
For example if a black hole has a companion star, gas streaming into the black hole piles up around it and forms a disk. (sciencedaily.com)
But the real problem, I think, is finding an economically and technically feasible way to capture the CO2 from an exhaust gas stream. (realclimate.org)