Water Purification
I love a sunburnt country as much as anyone, but the ongoing drought raises many concerns and causes much head-scratching over solutions. Grey water - the re-use of water from the shower, bath, or laundry, etc. - offers a good deal of potential for making more intelligent use of fresh water resources, so I was fairly excited to see this new toilet design on Beyond Brilliance, Beyond Stupidity. There are some ergonomic problems, but it's still good thinking.