This site offers pictures of the notebooks and journals of fifteen famous people. The specimens of Twain, Melville, Einstein, Edison interested me the most.
Looking at such things makes me feel slightly uneasy. There is not anything at this point that I can learn from them objectively speaking. It has more than a tinge of voyeurism — or so it seems to me now.
For a lot more of this sort thing, see this site. In the spirit of open disclosure: I dislike its name.
No further comment!