Here is an interesting simple wind power project of a small handheld wind powered Savonius turbine that charges your devices via USB port.
It has 3d printed housing and wind turbine with few electronic pieces and a small DC motor for a generator. The motor could be salvaged form old broken electronic devices.
It could probably be used outdoors in natural wind and indoors as a harvester on a AC unit. There are not many tests on it but it could be improved even if the original design doesn't work.
All the files and instructions: