See this site that runs competitions to demonstrate how rapidly games can be prototyped: http://www.experimentalgameplay.com/ . It arose from an interest by academica in game design and implementation (Entertainment Technology Center at Carnegie Mellon University).
Next competition starts Feb 3rd see http://www.experimentalgameplay.com/blog.php?b=686
Visual basic seems to be a common platform, perhaps prototyping would be even faster with newLisp? and give newLisp a profile in the area - any takers?
I'm not sure what gui framework would be best for this?
For a game example see http://www.experimentalgameplay.com/game.php?g=4 or http://www.experimentalgameplay.com/game.php?g=1.
Nigel