I am writing an essay about notpron, and I was wondering if anybody could tell me a bit more on the history of online riddles. Notpron was inspired by thisisnotporn, but was there anything before that? Notpron has also inspired a great number of new riddles, but is any of them popular/entertaining/innovating enough to stay around?
If you've got something interesting to say about the history of online riddles or if you know anything else that might help me, please tell me

Thanks!