Improv Everywhere – Human Mirror
If you haven’t seen some of Improv Everywhere’s videos, they are awesome. Basically, it is a group of people who go out into public places and do large-scale improv comedy.
In their most recent video, for example, they found several “twins”, got them to dress alike, and had them ride a crowded subway train. People’s reactions are great. Check it out:
And in case you have not seen the “Frozen Grand Central Station”, here it is. It’s my personal favorite:

