This sounds pretty damn remarkable. Free as well. Love to see someone use this to make a game 
from waxy.org
Quote
Three years in the making, Inform 7 is a radical reinvention of the way interactive fiction is designed, guided both by contemporary work in semantics and by the practical experience of some of the world's best-known writers of IF.
An easily learned but flexible one-window user interface makes the cycle of writing and testing rapid and painless. Inform creates, manages, edits, indexes, tests, and even helps to publish works of IF without fuss or screen clutter.
from waxy.org