Pass an imaginary ball - between two or group

Several variations on this one

Simplest is in Pairs , and passing an imaginary ball, dancing with it - changing its size, or shape and passing back.

As a group, its a good exercise in non-verbal communication, when sitting in a circle, reach into the pocket, pull out something imaginary, play with it, then throw it to someone else.  See if they pick up the idea. (Pick someone imaginative for first pass and then everyone will get it).