My nephew asked me to look for a big bungeee cord or a source for smaller ones to link together. Plan is to use it like a slingshot and shoot him on a skim board onto the surf zone. I figure rubber tubing might work or tied together bicycle inner tubes.
I would think a real bungee jump cord would take too much force to stretch far and have too short a pull. OIf course they must cost a lot due to insurance etc.
maybe rockets would be more fun or, a big pogo stick. how about a pile driver on its side?