Though nothing I do these days involves a helmet of any kind, if I was an extreme sports maven, I'd rock a Tunebug at all times. My skull wasn't the best speaker, but Tunebug kept it a safe one.
Would you ever wear headphones while driving a car? Of course not, it's dangerous—having your ears open seems like an essential part of staying safe while operating a vehicle. Now why would it be any safer to plug your ears with earbuds while riding a bike or a skateboard?
The Tunebug, by SVC, uses SurfaceSound vibrations to turn your helmet into a surround sound speaker, letting you keep your ears open to potential hazards around you. The unit straps to any helmet with three strong velcro buttons and can play music via Bluetooth or an aux-in plug. In the chaotic Pepcom convention hall the sound didn't exact rock my world, but it seemed like the Tunebug's vibrations would be powerful enough to give you a nice, audible soundtrack in calmer environs.
The Tunebug module detaches from its helmet cradle to turn any surface into a speaker. Look for the Tunebug Vibe for $70 in Q2 2010.