OHHHHHHHH... The worst party, "music"-wise, was this after-party for some fucking band (can't remember which), and some asshole started playing Sunn O))) out of his car. This was before I had even heard them before, BTW.
At first I thought his engine was just idling loudly, but then about 5 minutes later I heard the tone switch a little bit.
"Jesus christ, is this supposed to be music?"
"Its Sunn Oh"
"Its crap"
"No, you have to feel the music"
"I feel a headache"
Afterwards, just to check out what the hell I was listening to the night before in a reasonable enviroment, I downloaded an "album", and was subjected to about 20 minutes of something that sounded like feedback. I gave up and never went back. This also spawned a long time hate for the "band".