Automerge started as a research prototype and is now a widely-used substrate for building local-first apps: https://automerge.org/

Our GitHub has a boatload of experiments: https://github.com/orgs/inkandswitch/repositories

This is a fun afternoon just waiting for you: http://feelingisreality.com

Muse started as a research project and turned into an app: https://museapp.com/

Some of our essays have embedded versions of our prototypes you can play with:

* Crosscut: https://www.inkandswitch.com/crosscut/

* Potluck: https://www.inkandswitch.com/potluck/

Alex Warth is currently working on a remake of Ivan Sutherland's Sketchpad: https://github.com/alexwarth/sutherland

There's probably a bunch more I'm forgetting.