Found it !

Modularization will help tame the Squeak image a bit and may be critical to the long term success of Squeak. The image is getting very big, especially the Object class which is a bad place to be big.

The author of this invaluable tool set is Pavel Krivanek.

The download area.

An image map for the Kernel Image.

March 19 2009: Squeakland-EToys updated, see the EToys download page.
Updated July 10 2008: Pharo - new, leaner fork of Squeak. See related link.

From Wikipedia on Squeak Smalltalk: