The story of the 1967 version of Casino Royale is a very interesting one indeed; may be more enjoyable than the film itself.
Originally, Charles K. Feldman wanted to adapt Casino Royale as a straight Bond film, instead of the spoof we got. He even offered Connery 1 million dollars to star on it!
Imagine if Feldman manages to a serious CR adaptation. What would've been its impact on the "official saga"? Would've been sucessful? Would it start a rival Bond franchise? Would we still have Bond films today? And what if Connery had accepted to be in the picture: would it be his last, or would he feel more motivated to carry on?