I'm a bit paranoid about being seen by drivers when riding at night, and have been using a product called Tracer 360. It has a battery pack that lights up and flashes a number of different colors. The colored lighting is also transmitted through a pair of fiber optic cables that are worn as shoulder straps.

https://www.noxgear.com/tracer360

They are having a 40% off sale today with code PRIMEDAY17. They seem to have a similar sale once a year or so. I have no affiliation with this company or any of their employees. I've been using the product for the past three years or so and have been pretty happy with it.

I'm also intrigued by Tern's Vizy Light, a rear light that throws a halo of red light onto the ground. I haven't ordered one yet, but it does look very interesting. No affiliation with Tern, either.

Vizy? Light | Tern Folding Bikes | United States

Please feel free to post others that you've found interesting.