FringeTelevision.com has an exclusive look at the final page of the script for the Fringe episode Ability. In the episode, Walter is silent after typing the "Y" in "Ability", but in the script, he poses the question "Why?" Either way, it's clear that the ZFT manuscript was typed on the same typewriter, but it is still unclear who actually typed it - Walter Bishop or his lab partner William Bell.
Want more? Head over to the Fringe Spoilers section for another exclusive - the title to Fringe Episode 117.