I did this a couple months back and the responses were -awesome-.
It's a game I like to play when I want to write but have no idea what I want to write. So, I'll ask friends for a starting point. In this case, I'm supplying them for you ;-)
Starting point is a word, a phrase or an image.
You can use one or any combination of the three if you like. Whatever works.
Phrase: Everything you think you know.
Image: A half written letter
You write whatever you like using that starting point and see what comes. (Note, no rules on length, content, whatever. Just see what happens)
(Oh and, feel free to share this. In fact, I'd love it!)