The required "computer" class at my high school was basically a typing class. I took that first trimester (3 months long) my freshman year. I started that not knowing how to type properly with a WPM of about 15, and I ended that class at about 40 WPM, which was supposedly my cap unless I devoted time to typing. Later, I took a data entry job, which brought my WPM up another 5 WPM, and then, when that ended, I started my internet forum addiction in a way where it wasn't dependent on me doing something in a game and then posting it, and somehow brought my WPM up that last 15. Though I haven't tested my WPM since last August on my parents's crappy keyboard that sticks, so I don't know how much faster I've gotten.