Tone.js lets you build interactive music tools, synth apps, and audio experiments in the browser. Here are some ideas and open-source examples to remix, expand, or just jam with.
Use Tone.js's Sampler and Sequencer to build a grid-style step drum machine like 808s and TR-style gear.
Drag-and-drop synth components like oscillators and filters to visually design sounds and route signals.
Hook Tone.js output into a canvas or WebGL analyzer for reactive art that responds to frequency and beats.