My computer was cracked today.
I don't have the knowledge to make sure nothing was tampered with, and certainly not the time to do it (exam tomorrow and on Thursday). I guess I have been too lax about security issues.
Well, there was something good about it: Now I'll finally realize my project of setting up a linux box from scratch (something like Linux From Scratch, but I'll use environment modules as much as possible). I believe it will be a very valuable experience. I'll wait until after the exams, though.