Cool initiative @papa-pepper !!
Here's my contest idea :
A Game of Thrones (the HBO Serie) contest!! =)
Something like predicting what will happen in the next episode ( episode 1 of season 7 airs this Friday!).
I would say, that I make a (long) list of potential things/events/happenings that could happen, together with (un)probability points(from 1-10 how (un)probable the event is). The participants would have to pick from the list as many potential events as they want (which they think will happen in the next episode).
To be eligible for the win, the participant would need to be correct on every (!) of his/her guesses (picked events from the list). Between all the participants who got all guesses correct, I would sum the points of the events, the participant with most points (while all events must have indeed happened in the episode) wins.
The winner would get 10 SBD + 25% of the posts payouts (I'm not sure about this yet, maybe the winner gets more, maybe the runner-up gets also some SBD).
The contest would run once a week obviously, since every Friday the next episode of GOT airs.
I hope I can convince you with this contest idea, I'm open for suggestions & other similar ideas!! =)