I did this for years to learn computer graphics. I spent so many weekends and evenings building weird things that never made me a single dollar, but all the knowledge I gained eventually led to the job of my dreams. Here are some of the weird things I built:

- Tiny ray-tracer: https://github.com/diegomacario/Super-Sunshine - 2D rigid-body simulator: https://github.com/diegomacario/Dyna-Kinematics - Character animation system: https://diegomacario.github.io/Animation-Experiments/public/... - Animation curve visualizer: https://diegomacario.github.io/Animation-Magic/public/index.... - Motion capture playback in the web: https://diegomacario.github.io/Hands-In-The-Web/public/index...

That's a mountain of code that served one purpose: to gain knowledge.