Billy's one of the most educated people I know. If you read enough of his comments here and there, or even just look at how the little "off the shelves" blurb at the top of his blog changes over time, you get a sense of the depth of his reading. I won't go all gushy and say "he taught me everything I know", mostly because it's not true - I've done a hell of a lot of it on my own, and from picking little bits here and there from a lot of people, and figuring out how they all fit together - but I have learned a hell of a lot from him.
His "crazy" idea to hang out a shingle as "Philosopher at Large" isn't so crazy. Back when I was involved in Second Life, I considered doing just that in there, for pay. The problem with doing it in "First Life" is that there's probably a total of about 14 adults in my town who would even consider such a thing, and so the internet is a much more target-rich environment.
On the other hand, I've had some recent contact with the local homeschoolers. I decided to clean out my bookshelves - there simply isn't room to even store the entire collection - and so I donated 12 file boxes full of them to the group. It got me thinking that they are probably a market for just this sort of thing. I was thinking more in terms of teaching some C++, or at least basic programming, but they'd probably eat up some formal teaching in philosophy, or even informal discussions. And I've still got enough books left to run a lending library to some tens of these intelligent kids.