You can get a scanning-LED turn signal on your new model Audi, ... It’s not a complicated build by any means; an off-the-shelf WS2812B strip provides the blinkums, an Arduino Nano the smarts.

Here’s another Flora Arduino based project from [Becky Stern]. It’s a backpack with brake lights and turn signals for use when motorcycling, but it should work just as well for bicyclis… ...