This neat little cube not only cools you on a hot summer day, it'll stream you warm breezes when the weather turns cold. The desk fan/heater also looks really nice and is built with ambient LED lights ...

The controller uses one or more ordinary silicon diodes as a sensor, and uses a cheap opamp as the amplifier. I designed this circuit to use 12V computer fans, as these are now very easy to get ...

I'm converting a shed into an office and I want some air extraction to keep the temperatures under control in the summer. I've been looking at comercial extractor fans and can't find anything less ...