Spin-Ice and Other Frustrated Magnets on the Pyrochlore Lattice
  The recent identification of the dysprosium titanate compound $Dy_2 Ti_2 O_7$ as a ``Spin-Ice'', i.e. the spin analog of regular entropic ice of Pauling, has created considerable excitement. The ability to manipulate spins using magnetic fields gives a unique advantage over regular ice in these systems, and has been used to study the recovery of entropy. Predicted magnetization plateaus have been observed, testing the underlying model consisting of a competition between short ranged super exchange, and long ranged dipolar interactions between spins. I discuss other compounds that are possibly spin ice like: $Ho_2 Ti_2 O_7$, and the two stannates $Ho_2 Sn_2 O_7$, $Dy_2 Sn_2 O_7$. 
B. Sriram Shastry