Only because no one has said it yet, headphones. You can get a really great set of headphones for $200 or so, but if you want it to sound a little better you’re looking at $500-$700. But music can sound a bit better if you get better equipment for around $1200. Then you hear a $2000 set-up, and you chase that, until you hear a $5000 kit. And it just keeps going.