I don't come to photo section much so you'll have to bare with me if my suggestions were already given or have already been done in the past.
I'd like to see a long exposure contest. Focused object with an incredibly distorted, blurry, whatever background.
I think a water droplet theme would be cool too. Granted if you don't live near a waterfall, running water with high current, etc., it would be unfair to those. And I don't just mean water from a sink. I mean actual running natural water.
I love night time building shots too. Just buildings with lights on.
And I know it's not possible (at least as far as I know), but I've always wanted to bring a camera on a rollercoaster
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