Ask HN: how do you discover new music?

Well... the title says it all. Most of what I listen to came from hanging out with friends and parties, sometimes even from a car idling next to me in traffic. I guess that's called "old school" of acquiring personal taste in music. Very slow and time consuming.

I've tried using some social music sites too. Trying one out takes a lot of time and they usually end up recommending me what I already know and listen to (or used to listen). Or maybe I didn't use them right.

So, I'm wondering if there's something I haven't tried.