In-Alliance Competition Ideas

The vices of my alliance on s38 decided to have a weekly competition within our alliance. The prize being a $5 iTunes card. We just had our first competition yesterday, "Find my SubCity" ..everyone had a blast with the new excitement added. :-/ lol unfortunately I'm stumped for any other future competition ideas. Anyone have any ideas? Please help! Ty much.

prestige contest-try to get the most prestige over a week..requires a LOT of work..
riddle contest..first to solve..1 guess per person..
trivia..

the ones bahp said, but instead of simply prestige, it could be percentage of prestige gained, that way lower lvls have a better shot to get better