Low frequency helicity injection can, in principle, be used for current drive in a toroidal plasma system. The F-θ pumping technique is being tested in the ZT-40M reversed field pinch experiment. Two new methods of helicity injection without oscillating toroidal field are proposed for tokamaks. One method involves changing the horizontal position of the plasma in order to induce a poloidal voltage; the other method involves changing the cross-sectional plasma area. A zero-dimensional calculation indicates that both methods could be feasible for large tokamaks.