Yep, it is another one of those wacky inventions that will send droves to the comments section to decree it is doomed to failure. But at least its Australian inventor is optimistic enough to be taking out international patents on the design. Max Whisson's apparatus draws air  in past a fan , whose blades are cooled by the overlay of tubes carrying compressed refrigerant [right image]. The blades thus being colder than the ambient air temperature cause water vapour in the surrounding air to condense on the fins  beyond the spinning blades. This liquid water is then collected . Max, a retired medical specialist believes a four-metre square (43 sq ft) device could extract an average 7,500 litres (~2,000 gallons) of water a day. According to one news report, he says there are about 10 to 15 litres in every 1000 cubic metres of air, or as he adds: "An average-sized window with a gentle breeze flowing through it will produce a million cubic metres of air every hour." Max was, apparently, inspired by fog harvesting and the Namib beetle, both of which we've covered previously. Via ::The Australian, ABC Online and IOL.