In 2015, MCP and I made a light painting stick. It rapidly cycles 144 neopixels through all the lines on a bitmap image. Move the stick sideways while you photograph it with a long exposure and we’ve got some shiny light painting.
Once we got it working, we slightly lost interest. We should get back to it, make some art with it, as it would be great for long exposure digital graffiti and light painting protests.