  We present a three-dimensional lattice-gas model with trivial thermodynamics,
but nontrivial dynamics. The model is characterized by each particle having its
own random energy landscape. The equilibrium dynamics of the model were
investigated by continuous time Monte Carlo simulations at two different
densities at several temperatures. At high densities and low temperatures the
model captures the important characteristics of viscous liquid dynamics. We
thus observe non-exponential relaxation in the self part of the density
auto-correlation function, and fragility plots of the self-diffusion constant
and relaxation times show non-Arrhenius behavior.
