This is might interest a few people here. Pretty sure this will count as a modification to a helmet but considering this is more a safety feature will the cops be ok with it?
https://www.indiegogo.com/projects/brakefree-the-smart-brake-light-for-motorcyclists-motorcycle#/
https://www.indiegogo.com/projects/brakefree-the-smart-brake-light-for-motorcyclists-motorcycle#/