There’s an article over at Instructables that demonstrates how to create a jacket with built-in LED lights for bicycling at night. With the Arduino Lilypad prototyping board the lights can even be used as turn signals. This kind of project is way over my head, but it looks interesting nontheless.
Not everyone wants to look like an athlete while cycling to work or school. This cycling-jacket, made of hemp and wool, is equipped with lots of shining bright LEDs. It looks just as good during the day as it does during the night. Embedding the Arduino Lilypad electronics in the jacket, makes it at practical as it is nice to look at!