Why Is Smalltalk Dead
c2.com
c2.com
Pharo is a great implementation of Smalltalk, but Squeak has moved the Smalltalk ideas forward into new territory.
As one commenter in the article mentioned, there is Pharo. Pharo is open source and very good.
A warning though. Smalltalk is seriously mind-bending for those who come from more routine languages/environments.