I will define "extreme" in a moment.
Currently, as I'm writing this, someone on my college dorm floor has their (rap) music turned really really high, so the bass is going through the walls. I immediately thought to myself, "Man, what kind of classical music is out there that I could blast full volume, and its bass would be something really noticeable?" What pieces of classical music that you know would sound terrific with a subwoofer? Either really rhythmic, or just really loud and prominent. In other words, bass to the extreme.