Homemade Air Conditioner
MagPi's's Twitter account was asking if anyone has any good air conditioning Raspberry Pi projects, but so far no one has made one which is appalling in this UK heatwave (currently over 30C).
After some time into the conversation, this article popped up, and as you can see he has made quite a mess of the copper piping, but it gives you a general idea for how to build your homemade air conditioner system. For much more improved designs, I recommend you check out this article that showcases a much tidier way of wrapping copper wire around a traditional fan.
Bonus: Check out this Raspberry Pi article for a face tracking fan. Paired together, I think you could have your an incredible homemade air conditioner unit all to yourself.