Spoke beads are a novelty bike accessory that you can clip to your spokes. The 'loose' bead files will slide up and down the spoke and make a unique sound at low speeds. The 'tight' beads and the 'flag' will clip and stay in one spot.
These are not intended to be a replacement for reflectors and lights but they may help improve your visibility at night if you print them with glow in the dark filament as I did. (My favorite supplier here: http://amzn.to/1VU6ui2) (Sorry its really hard to get a usable photo in the dark!) The flags are big so that they make a cool color blur as you ride.
Printed with 2 perimeters on all sides, with 10% infill.