Over in Rockford, IL, some high school seniors pulled an epic prank. They collected a bunch of LimeBikes - it's a bike-share where bikes don't have to be locked into a station - and parked them in the high school parking lot - one bike to each parking space.
Not only is it a quality harmless prank... it also does a good job of illustrating how much space is required for automobile parking. According to the story (HERE), "Everybody had a good laugh, and the students moved the bikes to a single spot on the lot later in the day."
(I've heard of these "LimeBikes" before. Evidently it's a relatively new venture - and they have lots of startup capital. Based on the way it operates, with bikes NOT being secured, I can't imagine it's financially feasible - if there's not some way to secure the bikes, seems to me they will need to be replaced too regularly.)