As to my motivation for writing this:
Put me in a closed room with nothing to do (i.e., nothing to read), and within half an hour I am starting to have crazy ideas. The last time I used the train to get from Dagstuhl to Berlin (i.e., from a tiny city in SW-Germany to NE-Germany, a good 8-hour run), when I arrived at the Zoo station, I had filled about 15 pages of scribblings. Most of this stuff is long forgotten, but some of it haunts me. Like the Lambda-information-content thing. (Maybe because "information" is such a strange concept ;-)
By writing down the ideas, i exorcise them from my brain and ban them on a disk.