Not repeatable in that specific case, but have you thought about doing the same thing for other high-profile figures (either in finance or elsewhere)? You might be able to leverage your experience and success to get them to agree to a similar sort of thing...
I have thought of this but haven't really pursued anything yet. I also have permission from Buffett to publish his early partnership/hedge fund letters from the '60s, so will probably be doing that in the next year.
