This is my fourth roommate, but the first one who's really, really gotten on my nerves. I have been lucky with the roommate lottery (three of these four were not people I knew before rooming with them).

That does sound annoying, especially if you have trouble sleeping. Most computers I know have quiet keyboards. My current roommate sometimes stays up with really loud TV/music but fortunately this is an apartment (yaaay my own bedroom) so that really helps.

One of my roommates was a very sensitive sleeper - she had an eyemask, like you, and also earplugs - but fortunately I tended to go to bed before her, and I usually didn't give a shit if she was doing stuff (she was also very quiet and considerate).