Intel's Craig Chap showed a notebook powered by a sixth generation processor wake from a low standby power state. All he said was "hey Cortana wake up" and it started the PC.
This is possible with the help of Intel smart sound technology that listens for your voice commands.
The voice commands extend to ability to play the music on your PC. Once you wake your PC up, Cortana takes over and you can use all the standard commands.
Intel didn't mention how much power will this listening mode drain and how much it will affect the standby power.
The technology should be available with Skylake, sixth generation Core processors and notebooks that will arrive this year.