  A dimer mean-field model for the Ising spin-glass is presented. Despite its
simplicity it captures some of the essential features of the spin-glass
physics. The distribution of the single-spin magnetization is determined from a
self-consistent integral equation. By solving the self-consistency condition
numerically, we find that there are two temperature scales characterizing the
glass transition. At the first, higher temperature, the glass order parameter
becomes non-vanishing, and at the second, freezing temperature, it saturates to
its maximal value. The effect of magnetic field and the existence of the
Almeida-Thouless line are discussed. Finally, it is shown that the information
compressibility, defined as the derivative of entropy with respect to energy,
diverges at the freezing temperature. This indicates a zero internal
temperature and true glassy dynamics with diverging relaxation times.
