Metal and classical music for me. But to be more specific I really love progressive metal due to its sporadic nature and very odd time signatures. If you haven't checked out Dream Theater, I highly suggest it! They're my favorite for sure. But I'll listen to anything that's "different"; check out The Dear Hunter too (they're not metal... But I'm not sure what their genre is... maybe progressive alternative?) But if you want some classical music that's brutal and beautiful, listen to Bach or Beethoven (my favorite composers for sure!)
Basically anything without a typical formula or structure.