Memories come flooding back. PowerMops - an integrated Forth environment for the Macintosh - is now also available for OS X. I haven't looked at it in a long time, but the description still sounds as cool as it did back then. Direct native code compilation and integration with the various toolboxes and nowadays also with the Cocoa frameworks. And all of this in an object-oriented Forth.
I found the original article at Planet Lisp.