There’s a great thread over at Quora with photos of famous people in unexpected places, situations, or company. For example, there’s a photo of a young Bill Clinton meeting John F. Kennedy and one of Mark Twain and Nikola Tesla hanging out. My two favorites are a photo of Tank Man captured from an unusual angle and a chilling photo of John Wilkes Booth at Lincoln’s second inauguration, taken a little over a month before he killed Lincoln.
See also awesome people hanging out together. (thx, david)