  We experimentally demonstrate that supersaturated solution of sodium acetate,
commonly called 'hot ice', is a massively-parallel unconventional computer. In
the hot ice computer data are represented by a spatial configuration of
crystallization induction sites and physical obstacles immersed in the
experimental container. Computation is implemented by propagation and
interaction of growing crystals initiated at the data-sites. We discuss
experimental prototypes of hot ice processors which compute planar Voronoi
diagram, shortest collision-free paths and implement AND and OR logical gates.
