"5-photo collage - mount your camera on a tripod or something firm and point it towards the street and take five shots at 5-minute intervals and make a collage of those shots in the order they were taken. or maybe go to a park or the front of a store, anywhere where there is constant activity. the camera should not be moved, it's just to record what happened in that five 5-minute intervals."
Yes, I know it's six instead of five. And, no, I don't own a tripod and nothing flat seemed to be at the right height, so I stood in one spot and tried to line up the shots by using the tall pole on the right. I set the timer on my iPod for five minutes and when it went "boing!" I took a picture and reset the timer.
I thought this would be easy -- lots of interesting people at Crypticon. But the doorway I planted myself at ended up to be relatively boring. People were coming and going somewhat, but I had picked the wrong vantage point and spot to aim at. And the really interesting folks were gone by the timer went off. I tried again shortly afterward, inside that time. (See the collage posted to the 16th). The pictures weren't taken until Saturday the 17th, but I have a lot of days to fill in.