That is a more serious question than it first appears at first glance.
Firefox, GCC, cat, gzip, PovRay are all things that should be potentially doable. Each one will not necessarily _have_ to be done, but the idea should be embraced to see if they are possible. If there is any reason why these things are impossible, that should be an area to focus on. Why is it not possible? Should it be possible, and if so, how to make it possible.