A fun energizer in which there is a lot of physical contact and people can laugh a lot is ‘The Knot’.
Give this instruction:
Stand shoulder to shoulder in a small circle.
Close the eyes, put the hands in front at the height of the shoulders.
Look with closed eyes for the hands of other people and grab them. When everyone has found two hands the eyes can be opened again.
Now the knot has to be untied WITHOUT releasing the hands!