Any big city bicyclist knows that being small and silent on the street is a deadly combination. Drivers of 2-ton cages are simply immune to anything but the sights and sounds of combustion engines riding four on the floor. This issue affects silent-running hybrids and compact electrics too, something Japan's government is taking seriously in a new government review that could result in a mandate for the inclusion of "a sound making function" in their future eco-rides. Safety aside, we presume Japanese manufacturers would choose a sound that's as tasteful and unassuming as their locally brewed hybrids. Imagine if GM was to make a similar decision... oh, right.