The effect of electric fields on the phase diagram of binary fluid mixtures has been the subject of intense research in the past 50 years. Starting from Debye and Landau & Lifshitz, experiments and theory have shown that electric fields can change the critical temperature of a mixture. However, the change to Tc is so small (about 0.01 degree) that there has been disagreement even about its sign. Here we show theoretically and demonstrate experimentally that non uniform electric fields can induce a phase transition in a liquid mixture of two non-polar fluids under practical conditions. The effect is huge and occurs at 1 degree or even more above the transition temperature. Possible applications are in microfluidics, light scattering and guiding, eraseable writing, controlled chemical reactions and electro-rheological devices.