<s>[INST] what's that thing they invented for the developing world where you put it on a dirty lake and the sun rays evaporate the water and it goes up and into a container and it's clean [/INST] Are you thinking of a solar still? Forms of it have been around since the Inca Empire, but there have been recent iterations targeted for remote areas with frequent or severe droughts.</s>\ <s>[INST] are there other solutions like that ? the name doesn't ring a bell [/INST] 