Using the high-frequency Floquet theory of laser-atom interactions we predict that in superintense fields a proton can bind more than two electrons. For linear polarization, a self consistent solution of the structure equation shows that H2- becomes bound for α0 = 155 a.u. The fields and frequencies needed for binding H2- are within reach of lasers under construction. By choosing appropriately polarized bichromatic radiation, the production of more highly charged negative ions also lies within experimental reach. The ions are (adiabatically) stabilized against ionization, from their very appearance.