A new solar desalination system takes in saltwater and heats it with natural sunlight. The system flushes out accumulated salt, so replacement parts aren’t needed often, meaning the system could potentially produce drinking water that is cheaper than tap water.
Might be really useful for costal areas that have their water systems knocked out. It might save some of the gajillion plastic bottles that are deployed in emergencies now.
It looks pretty cheap to manufacture and could by done DIY.