If they come down in price by a factor of 100, I could buy them, take the aluminum frame to the scrap yard and make a profit!
But really, even if the cells come down to 10% price, the other things like front glass, rear material, frame, wire, plastic, boxes and packaging, warrantee issues, labor, shipping, and profits will still be there. Even if the cells were free, I can't see the price ever going down more than 1/2.
I make a poor living doing these wierd solar things, for a niche market. Pay back time for most of my customers is 3 to 5 years. That doesn't even include avoided repairs to the troublesome systems I'm replacing. It also is eaisier then the replaced systems. I'm only taking money, let alone all the enviromental issues.
And my state has no credits to make it cheaper.
My typicial installation costs the same, +/-10% as the same gas powered system. But there is no gas or repair costs, no baby sitting the gas system, no break downs, and no noise. Which would you want?
I have a 15 year old solar and battery powered calculator. The batteries have been dead for years. I use it every day. If it's light enough to see, it's bright enough for the calculator to work. It takes 2, $3.50 batteries. I never replaced the batteries. How much money have I saved? I have no idea, but a lot.
Solar is not a pipe dream. Even now, for some applications, it the cheapest way to go. Cheapest means people will use it, and they are using it, more and more.