#physics **Snowflakes** These remain nearly impossible to grow in the lab, except the guy who grew a single flake on the tip of a rabbit hair. The physics of doing it on-mass is amazing, and hasn't been done, as far as I know. Every time you try to form ice crystals, you'll get everything but a snowflake.
Actually doing it would require a hypothesis, and a risk of falling flat on your face. Nobody will do this....