I go between new age to ambient techno to dubstep. A really good site for classical is Radio Klassik Stephansdom. I don't speak German so it's all noise to me. I heard and old drum and bass track I forgot about so I may try that again.
depends on what I have to do. cleaning up beat or metal. mindless repetive stuff (fast) electro (without lyrix). for studying I have to find that one song and then it is hyperfocus time