Dark Matter from Supersymmetric Grand Unification
  In constrained minimal supersymmetry the lightest neutralino of bino-type is the only neutral candidate for dark matter. As a result, one is typically able to restrict all the supersymmetric mass spectra below roughly 1-2\tev\ {\em without} imposing an ill-defined fine-tuning constraint. 
G.L. Kane, Chris Kolda, Leszek Roszkowski, and James D. Wells