Brahm's Hungarian Dances, No. 17 in F-Sharp Minor. I don't actually want to be listening to it right now (got a bunch of new albums I've been itching to give a spin), but the specific arrangement of my domicile coupled with my sister who claims music with lyrics renders her incapable of studying = me playing pleasant classical while I do other stuff.
I'd just put on headphones, but I'd rather not tether myself at the moment and they start to hurt after a while.