We present a new approach to subwavelength optical confinement, based on hyperbolic media in planar Fabry-Perot geometry. Unlike higher-order resonance modes in indefinite metamaterial cavities, the predicted resonance corresponds to 0th-order mode and can be observed in planar systems. Our approach combines subwavelength light confinement with strong radiative coupling, enabling a practical planar design of nanolasers and subwavelength waveguides.