The Dumbest Idea I've Shipped This Month I built a thing called The Mood Ring Playlist. It points your webcam at your face, reads your emotions, and generates a live music track that shifts as you do. Smile? Tempo kicks up, major key, bright pads. Scowl at your code review? Minor key, slower, a little more low end. Zone out completely? It drifts into ambient territory. This article is the "why w