The Flexy reminds you of the simple joy cardboard can bring. Shaped and pieced together from cardboard, it is designed to work like the famous metal slinky.
Made out of recycled materials this biodegradable toy is said to do all that its metal counterpart can, but with the obvious benefit of decomposing when everyone has finally had enough. The Flexy will then happily ‘walk’ down your stairs (though wont make that jingle jangle slinky does) and comes with instructions to make it move in many different ways from flinging to a rippling rainbow, it can even be moved into place to create many different sculptures.
The Flexy is not quite as compact as its metal counterpart measuring 11.5cm x 10cm x 7.5cm (4.5in x 4in x 3in) closed up and 25.5cm x 10cm x 7.5cm (10in x 4in x 3in) opened out fully, though it should hopefully not tangle up like a metal spring likes to do. Though it claims to do all its metal counterpart can do I am not sure how well it could be used in science classrooms to show easily the difference between light waves and sound waves, but it is certainly a more environmentally friendly way of laughing at something falling down the stairs!
Source: Craziest Gadgets