The M5 Switchblade sports a built-in rechargeable power system. That means it can be more easily integrated with other electronics gear, like Bluetooth devices and head lights.
An integrated power supply enables existing helmet electronics to be made smaller, last longer, and have more range due to the increased power output (up to 7.4VDC). Auxiliary electronics and systems made to work on or with a crash helmet no longer need to carry their own power supply, the crash helmet now is the power supply!
These helmets are being used by law enforcement now, and will soon be available to the public according to the company's managing director (who sent this our way).
M5 Switchblade [Product Page]