Visualization + Multi-user

I have tried several times to create a project combining these two aspects of software development, namely:

https://quiet-forest-75069.herokuapp.com/

A shared-solitaire system where everyone can watch and move the cards.

Several attempts at chat systems and a chat system with plug-in "channels."

An attempt to make a multi-user IDE out of a single user IDE.

Shared graph editing system with different views per-user.

Only the IDE went forward for several years, and my company stopped putting money into it after the main development was over (even though I had ideas for extending the user interface/language). In other words, we met the initial requirements too well, and there was no further marketing. Documented here: http://www.dsmforum.org/events/dsvl01/carlson.pdf