Incorporating both the magnetic leads and the underlying semiconductor, a spintronics circuit could hold its memory when turned off, as the magnetic elements remain magnetized. Manipulating spin could also require far less power than steering charges does, says Ron Jansen of the University of Twente in Enschede, Netherlands. Some physicists even aspire to create a spooky quantum connection called "entanglement" between spin-polarized currents to make a quantum computer that could crack problems that stymie an ordinary one.