This crowd breaker will work better with a smaller group (10 or less). If you have more, you can split into two or three groups.
Have everyone stand in as tight a circle as possible. One person in the group will be in the middle. Have them cross their arms across their chest to touch their shoulders. Then instruct that person to stand perfectly stiff (this is essential) and close his/her eyes. Then this person will simply lean one way or the other. Whoever he/she starts to fall toward will push him/her back to the center of the circle. This continues until the one in the center gets tired. Choose another volunteer and start again.