Some years ago I worked at a company where there wasn't an aircon in the office and the manager didn't give us a permission to work from the server room. Didn't allow us to buy an office fan either. I dived into to the skip, where we used to throw away electronics and made this, out of discarded PSUs.     Most people said it will be a all-show-no-go but surprisingly it had some punch and I used it for quite a while. I planned to make it bigger (16 fans) but as soon as I started working on the frame the heatwave went away. If I look hard enough I might might a video when it was operational. It was oficially PAT tested and you can see the sticker on the right side. Whether it would pass if tested by another person is entirely different matter 😉 Few years before that I made a scaled down football stadium (pitch, stands and everything) out of old harddrives. I can't find the photo atm though. ... View more