You can't open source an ASIC. It's not the design that is expensive. It's the production.
If mining isn't economical for individuals, it's not going to be economical to large companies either. That is why we have dynamic difficulty.
The difference is that the companies, that can create asics, are selling them for very high prices. So that buyers wont ROI. The company itself can roi since they only have the production cost, a customer would pay much more of course. Otherwise it wouldnt make sense to sell the miner.
If the production is the expensive part then there might be a solution. What about a groupbuy collecting bitcoins. Then paying the design with it and with the rest of the money chips are ordered. Everyone gets so many chips like he put partially bitcoins into the project.
At the end every investor has his own chips and the design is there. Of course if would make only sense if many people invest so that each investor can get relatively many GH and doesnt have to pay much for the design partly. So that every initial investor gets his reward. The chip design could be open sourced then and future orders of course wouldnt be so profitable anymore. Thats why every investor would put most of his money in the first investment.
