Just experimenting with this :
here You need flash to hear anything...
I was wondering if this kind of feedback brings greater accuracy to beginning touch typists. You would not only get feedback from your fingers via the keyboard and visually from the screen but also from your ears. One could actually make it so the sounds are output from the keyboard itself.
EDIT : I used short phonetics for all 26 characters. My 6 year old son likes to type on it now... :-)
What could also be nice is to have a word recognizer which utters the words when typed, that way you would 'hear' you misspelled or mistyped something.
Regards.