Sock bubbles...a pinner wrote "it took 3 mins to make & is soooo cool. The kids are gonna love it! Our favorite pinterest find yet!"
Also on these boards
Making bubble snakes: Simple, easy and made with thing that I had laying around my house. Perfect! All you need is an empty water bottle from your recycling, duct tape, a sock that is missing its match (which we seem to have an abundance of), dish soap and some food coloring.