Re: Who will compile my open source UPS?
Actually, if you published the gerbers for the circuit board, some people would make their own and others would produce complete boards for the ones who can't. And if your focus was on component suitability, rather than the lowest cost solution, some parts could be sourced complete. For example, there are all kinds of smart battery chargers available in all sizes. As far as batteries are concerned, I'd be surprised if you couldn't find common components sourced out of China on eBay. Even without that, batteries with the same characteristics are going to be available just about everywhere. Supply chains are worldwide.
I've been appalled by my growing UPS graveyard. So much so that I stopped buying APC. Rather than going this route though, when I remodelled my house I isolated circuits. Lights, computers, etc on their own dedicated circuits. Which means I can pull them out of the primary circuit panel and connect them to one supplied by batteries and an inverter. (primary charging by solar, I still need a circuit to initiate charging from a grid powered charger when capacity drops below a certain level and no renewable charging is available) My power requirements have dropped since I moved from compact fluorescent to LED, but a down side (since I am currently still powering lights from grid power) is that state changes in LED is much faster than CF or incandescent, resulting in flickering from dirty power being much more noticeable. Thus my desire to have all my ceiling lights powered by battery full time.