  We show by means of experiments, theory and simulations, that the slow
dynamics of coarsening systems displays dynamic heterogeneity similar to that
observed in glass-forming systems. We measure dynamic heterogeneity via novel
multi-point functions which quantify the emergence of dynamic, as opposed to
static, correlations of fluctuations. Experiments are performed on a coarsening
foam using Time Resolved Correlation, a recently introduced light scattering
method. Theoretically we study the Ising model, and present exact results in
one dimension, and numerical results in two dimensions. For all systems the
same dynamic scaling of fluctuations with domain size is observed.
