Protecting your noggin — along with other parts of the body — during physical activity is essential if you don't want to end up in the emergency room. The problem is that big bulky pads and helmets can be cumbersome and uncomfortable, not to mention way too dorky-looking for style-conscious kids and teens. Nailing these two birds with one high-tech stone, a British company called d3o has developed a special elastic polymer that remains soft and pliable under normal conditions, yet stiffens almost instantaneously into a hard resilient layer when impacted at high speed. By cleverly incorporating itself into stylish activewear, the d3o material can remain practically unnoticed, yet will provide true protection in the case of a sudden mishap.

D3o doesn't make finished products, but sells the material to sport-gear manufacturers like Ribcap, Globe Shoes, and a company called Spyder, which used it in the ski suits worn by the U.S. Olympic team in Torino. — Michael Trei

Via CNN