Science
I studied physics and mathematics and occasionally computer science and for some reason I study geoecology now. Well, that happens to be what you for example can study if you are working on your PhD in environmetal science, impact modelling. I like that, I just didn't see that coming although I always was an environmental activist more or less. Now I also am a Scientist4Future and on the 36th Chaos Communication Congress I will be a speaker. You can find materials and such below.