What's the easiest way to create a software-controlled 220V electricity interruptor?
I found several USB controlled relay modules, but unlike many others this one does not require a separate power supply; it's powered from the USB bus.



The module uses a virtual COM driver to control the relays from your PC. So any programming language able to talk over UART can be used to control the module.

On the same site you'll find modules with 8 relays as well.