Examples? There are 1-Wire, Power over Ethernet, AS-Interface, and others, and this TI application note describes a way of doing it with several possible two-wire connections.
And yes, it is used often.
As far as I know, none of these do it the way you describe, though, and to be honest, I don't see the point of doing it that way (by shorting the combined data line / power supply to ground to send a 0), but maybe I am missing something.