Tires were the original reason that Kevlar was being researched, because they needed something lightweight but still strong enough to hold up on the road.
Kevlar is often used in helments along with other materials to provide the strongest head protection currently possible.
Bulletproof vests are often used by the police and military. The fibres are woven tightly enough to be strong enough to not allow projectiles through yet the fibres are still light enough to not encumber the wearer like other materials tend to.