Summer is here for those of us living in the northern hemisphere, and it does get pretty hot out there during the afternoons. For those who have yet to purchase an air conditioning unit but always wanted one, how about putting those two hands to good use by building one yourself? Of course, it will be nowhere near an real AC unit where cooling power is concerned, but the raw materials required to build one are pretty rudimentary – we’re talking about a cooler, a fan, some tubes and a water pump. All you need to do is run cool water in front of the fan for it to cool off the air that blows out, making it slightly more effective than a regular fan.