Public Enemy's Chuck D...he actually follows me, which is insane to me. I have no idea why.
Michael Moore...he did an AMA on Twitter maybe 5 years back. Everyone was asking questions about politics, so I asked him instead about whether he thought there would be enough demand for an Amtrak line from Chicago to Traverse City, where he lives.
Sarah McLachlan...she was working with some ballet company, preparing some of her songs for a short dance program they were doing to her music. I had a question about the process (don't remember what, tho) and she answered it.
That's what I remember. Could have been more, but they've long since slipped my mind.