People spread around the room and lie down, and are
told that when  the music starts they should wiggle like worms to the
music. Place a portable tape player somewhere near the middle of the room and
start it playing.

Of course the fun part is that to all get to the music you have to make a big
wiggly pile.

As a variation, you can ask people to dance, then close eyes, then get low,
then move - low, but not necessarily as a work, towards where they think the
center of the room is, usually people end up touching, but if not ask them to
reach out and connect with two others. Then stand, keeping moving, often this
morphs into a contact-dance. Then gradually move aparty.