The Bugged Dev built an electromagnetic-field visualization with Claude Opus 5.5. The pitch is modest: physics is easier when the field is something you can see move.
Riding the jelly trend, Ann Nguyen built a virtual jelly dice roller in Three.js with Claude Fable 5.1 — pick how many dice you need and the style, then roll.
Scott built a Jelly Baby game in three.js with GPT-6 Astra, after people would not stop watching the bouncy jelly. It is playable live, and the source is open.