Hesiod

I love this project. Otto's expertise and personal commitment to this project are beyond exemplary, and he's made it into an open-source offering which knocks paid-for products like Quadspinner Gaea and WorldMachine into a cocked hat for the use cases it targets. The variety and sophistication of the algorithms are extremely expressive and focus on trying to let the user do anything he or she can conceive no matter how bonkers, rather than presupposing that e.g. game terrains or scenic artwork are of priority. This does admittedly and necessarily mean something of a learning curve. Linux support, progressive improvement of "boring" but important aspects such as stability and memory management, and engagement with the users put expensive commercial offerings to shame. It seems churlish to say that I'm hoping to extend it with one or two things I'd like to speak particularly to world-scale terrain creation, but that this is possible is a major step forward as well.