[ 1 ] was opencroquet.org
Smalltalk leads to Squeak, the open source implementation, and through one if its main contributors (Alan Kay) leads to the Croquet Project. I don't even know where to begin to describe this project. It's an open and programmable 3D environment designed for communication and collaboration. Or something. You have to see it to believe it. And maybe not even then.
Smalltalk -- The language Croquet is written in and uses.
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