Hi guys. I've been thinking about making Squeaks UI more easily
extensible these days. Brian T. Rice clued me unto CLIM, a smart UI
infrastructure for Common Lisp. Like everything about CL, I find it a
little alien but in a "deep thoughts" kind of way.

Nice screen shots -
http://kogs-www.informatik.uni-hamburg.de/~moeller/uims-clim/clim.html

Dense intro -
http://kogs-www.informatik.uni-hamburg.de/~moeller/uims-clim/clim-intro.
html

Paper about LGPL implementation, includes differently dense introductory
material.
http://www.bricoworks.com/~moore/clim-paper.pdf

In their textual UI, for example, output is not printed, it is
presented, so that the presentation is aware of its underlying meaning.

As a nice start we could do in this direction, think about having a
print it variant that attaches a Text attribute to each string that
holds the identity of the object printed, and for example, lets you in
the menu create a variable for it or open an explorer on it.

Input is also smart - they have type-aware autocompletion, so it knows
what type the arguments should be, and highlights literals on the screen
which are approriate, so that if you click them, they become input. 

Daniel