I'm one of those people who have to vent hard or else I'll bottle everything up and explode, so I "actively" meditate.
I usually pump some hard rock or heavy metal and either do some of the best workouts I ever do, shadow box or simply visualize some ass kicking if my body's thrashed. Either way, my mind and consciousness go out the window and I'm left with nothing but the music.
It doesn't leave me refreshed and at peace sometimes, but it does blow enough steam out of me that I'm calmer and able to function to some better degree.
Btw, good luck with finals! I'm majoring in broadcasting and busting my butt off, I wouldn't survive a half semester in law school!