Current approaches are reviewed for developing an rf source for driving the Next Linear Collider (NLC) based on various gyroresonance interactions. An alternative mechanism is described, with the potential of converting 2.85 GHz power from a SLAC klystron to output at a harmonic ranging from 11.4 to 31.4 GHz. Preliminary calculations show that this new process can enjoy high conversion efficiency, strong resilience to axial momentum spread on the beam, and weak power flow into competing modes.