Game Design Tools - Machinations
I haven't ready the entire article closely yet, only glanced, but the theory of it seems pretty cool. I can imagine tools like this making life a little bit easier for the coming generation of game developers as they won't have to use painful spreadsheet formulas or wait to run simulations in the games themselves.
But, as useful as this could be, we'll also likely start to see a more accessible tool-set in development meaning that you can run your own tests much easier and it an isolated environment. And in addition to this, the modern day game designer is often encourage to have basic coding skills. So how long this could prove to be useful is unknown. Regardless, it's still interesting.