Roommates

I can't say my roommate and I are particularly friendly.  We only occasionally talk to each other and I can probably count the amount of actual conversations we've had on one hand.  She does a lot of things that bother me but I keep my mouth shut because I don't want to start problems.  Last night I was up late doing work and usually she stays up later than I do on her computer and playing music.  It's not that loud but I really can't sleep if there is any light or sound.  I was on a deadline for an essay which I was trying to finish and she asked if I would be up much longer.  I said I wouldn't because I only had a bit more to go.  Maybe ten minutes later (and I only had 50 more words) she asked when I would be done.  I said 50 more words and then she went on to say that it was late and my keyboard was loud and that it was inconsiderate and I had all day.  I said I cleaned the entire room and had other work.  She left the room, I finished and then went to bed.  She came in later and surprise surprise, still had the music on.  If she wanted to go to bed that bad, why would she keep her laptop music running?  I know some people fall asleep to music but usually if they, y'know don't have a roommate. 

So yes, my staying up was disturbing her and I would usually feel bad about it but my last roommate stayed up until after 4AM studying once when I was trying to sleep and I didn't throw a hissy fit.  Honestly, it didn't bother me that much because she keeps me up most nights, she left her milk spilled in my fridge for about two weeks (and that's only after I finally decided she wasn't going to clean it so I did) and it leaked out of the fridge onto the floor, she undresses completely right behind me (sorry I don't feel comfortable around naked people- especially if I barely know them), she barely talks to me, she turns her computer volume ridiculously loud to watch Hulu so that I can't even hear the volume on my own computer, she was ungrateful when she kicked me out of the room so she could sleep with her boyfriend (she bitched because I didn't give her another night), she Skypes her boyfriend all the time and talks to him with a huge lisp (how is that supposed to be cute???), has people come into our room who also completely ignore me, she rarely washes her hands after using the bathroom, etc etc.

So what are your roommate horror stories and what do you think makes a good or bad roommate?