Noticed a really weird sound coming from my rear passenger side wheel... kind of like a grinding, or more accurately, the sound you get when driving over hard pack snow and ice, kind of a combination between grinding, rubbing, and crunching. It's ugly. Doesn't seem to go away with speed, but it doesn't become obvious until about 30km/h (20ish mph) Gets worse when I hit bumps or make a left hand turn. As far as I can tell, its only from the passenger's side. Hitting the brakes doesn't really make it go away, neither did the parking brake.
I have no idea what caused it. I've been on these shitty 1st gen TSi AWD winter rims for 3 days but this problem was only noticeable this morning. The only thing I can think of that would cause this is my buddy's bright idea to pull the e-brake full on when I was on an icey road and lock up the rears.

Bearings? froken brake? bushings? how can I tell?

Take the wheel off and look

Whoops i was going to say check your rear upper knuckle bushing but re-read your post. Yeah take off the wheel and see whats up.