I dunno Juan, the $100 price is based on giving them away to kids in deeloping countries. The plan is kind of vague, but the article mentions selling them here for $200 and then $20 or $40 going back to making them available for cheap in developing countries. I'd buy one for $200, or even more, under those circumstances.
It's about time that somebody found a way around the tyranny of technology. I'm kind of surprised at the idea of open-source hardware though.