Natalia Ares and co-workers writing in Nature Physics show that electromechanical back-action electron-phonon coupling for a single electron transistor can be coherent, analogous to a laser. but where the optical field is replaced by a mechanical displacement. Real-time measurements of a vibrating carbon nanotube transistor pumped by an electrical bias shows phase and amplitude coherence, as well as injection locking, classical squeezing through anharmonicity and frequecy narrowing through feedback.