Chat. A lot.
I never received any touch-typing training. Infact, when i first started, i had to search the keyboard for the key... Now after 7 years of IMing, its all muscle memory. I have never tried to speed my typing, but a lot of times it just flows without me even realizing that i am typing as i think. Also i have noticed i can type in my usernames and phrases i often use a LOT faster than the other things.
This may or may not have been a useful answer.