Actually, this idea converges with one I've been toying with for a while, though it involves more than autism friendliness. I have been considering what would be necessary to establish a self-sustaining community, and considered that the talents and focus of autists would be well suited to doing just such a thing. The question I've been considering, and that I almost started a thread about, is which skills and resources would be necessary for a community to be self-sustaining? It would just really rock my world to live some place where I could say, with all honesty, "Your money's no good here." And yet, it is a slippery slope. There have been many utopian endeavors that came to unhappy ends.
I'm actually working towards doing the same thing - planning on creating a self-sustaining house on a large property, then expanding from there.
One of the skills I've been researching are cheap and effective building materials like papercrete, which is 20% sand, 20% concrete and 60% newspaper - you can use it to make usual looking "brick" structures, or more exotic structures like this:

I've also been looking into grey water disposal and sewerage recycling systems, electricity generation, etc.
I worked out early on that we'd still need to make a small amount of money, as some mod cons I just couldn't live without (like broadband, books, a car), and also some things would be more trouble than they're worth to self-sustain (like milk - one cow or goat would be unreliable, and more than that would take too much resources in a small community. Especially when it's as cheap as it is to buy. Also toilet paper, shampoo and conditioner, and more exotic building materials like fencing wire). So before we can do it, we're working on some internet projects to make a small amount of money.
We're probably too far away to collaborate, but if you were interested in looking into setting a community up for real over there, I'd be happy to swap ideas...