Object Arts Ltd.: Makes Dolphin Smalltalk. Product set based on a modern implementation of Smalltalk development environment geared to make programs for Microsoft Windows operating systems. Download free older versions, and software

Squeak.org: Free, open source, open research, super portable, new Smalltalk-80-based language, written in itself, by Smalltalk's inventors, the (nomadic) original Xerox PARC, Alan Kay team, now founding the Viewpoints Research Institute. Runs on 22+ platforms, hardware and OS. Now hybridized with the Self language's Morphic User Interface Toolkit

Squeakland: More than any website so far, this one implements the largest piece of the original Xerox PARC Learning Research Group's vision for programming and education. Free downloads: run Squeak from in a Web browser (free plugin), software, program sharing/exchange areas, Alan Kay essays

SqueakSource: Hosts many projects, supports distributed development, via smart Monticello code-repository; similar to SourceForge