The Hövding is an airbag for cyclists, bringing the now-standard technology found in cars to those who prefer to travel on two, rather than four, wheels. Worn like a collar, it remains deflated until you're involved in an accident, at which time it will inflate in under 0.1 seconds to protect your head.
It works by inflating with helium when it detects the abnormal movement that is associated with cycling accidents. A black box recorder is also embedded within the airbag collar to record the 10 seconds of data captured just prior to, and during, an accident.
Each Hövding airbag collar costs €399 (US$540), meaning it's a pricey alternative to more conventional helmets. That price gets you the combination of the collar and a shell; the latter being designed to mask the collar in a fashionable outer layer.
Source: Gizmag