For instance. A challenge (off of the top of my mind) could be spray paint the NS logo somewhere on a school. The challenge should not be directed at one specific person, but out in the open, so everybody can compete. Then when someone posts a picture of said graffiti, they get rewarded.
Everything happens in this thread. New challenge suggestions, and then proof.
* Must not be ns related. can be... dressing your cat up in jiberish.