At a Hackster.io Hardware Meetup - SF, we made bicycle lights. Although I finished it and housed it in an Altoids tin, it wasn't wasn't solid enough.
After a month or so, I decided to build a more robust version. The circuit was the same but the housing was much different. I designed a 3D printed housing for the LED strip and the circuitry. The power bank sit on top. Plug in the USB cable and it begins flashing.
The complete build and video can be found on Hackster.io.