  We theoretically propose a scheme for a spin quantum bit based on a double
quantum dot contacted to ferromagnetic elements. Interface exchange effects
enable an all electric manipulation of the spin and a switchable strong
coupling to a superconducting coplanar waveguide cavity. Our setup does not
rely on any specific band structure and can in principle be realized with many
different types of nanoconductors. This allows to envision on-chip single spin
manipulation and read-out using cavity QED techniques.
