Today's geegaw is a rear light that looks (to me) like it should be transporting uranium isotopes or frozen bio samples.
Vizy is a rear light from the Tern Bicycle people. It sends out a bright light (60 lumens) behind the bike for cars to see, and also sends a 360-degree circle of light around the bike to make it more visible and recognizable for the people around it.
It's very reasonably priced as lights go. USB rechargable. website