Pongo is a free MSN instant messenger client written in Smalltalk. It is cross platform, running on Windows, Mac, intel Linux and several other unix implementations.
Swazoo (Smalltalk Web Application Zoo) is an open source, vendor agnostic, dialect neutral Smalltalk HTTP server with resource and web request resolution framework
Abora is a hypertext system supporting fine-grained links, transclusions and user link filtering. It is inspired by Ted Nelsons Xanadu and Udanax-Gold by XOC.
Squeak is an open, highly-portable Smalltalk-80 implementation providing platform-independent 2d and 3d graphics, sound, and network access. Active development of Squeak is going on elsewhere than SourceForge now, meet us at squeak.org.
Daitanmarks is a web application for sharing, storing and organizing bookmarks.
It is written in Smalltalk and can be easily estended and edited.
Best, you can run it on Unix, Windows, MacOs!
DaitanMarks is a Swiki web application.