I guess networking would be the largest cost. How are these going to access a network? It will be using mesh networking, which I'm sure will be a great benefit, but only if there is that larger connection to an outside network. It would be cool if there was a wikipedia image in the memory (with correct local language). But for application and support cost, it is using free software and I doubt there is going to be much need for support, other than a repair center of some sort. Overall, very cool, but maybe Gates wanted his software on it instead.