  In these lectures we describe the use of Monte Carlo simulations in
understanding the role of tunneling events, instantons, in a quantum mechanical
toy model. We study, in particular, a variety of methods that have been used in
the QCD context, such as Monte Carlo simulations of the partition function,
cooling and heating, the random and interacting instanton liquid model, and
numerical simulations of non-Gaussian corrections to the semi-classical
approximation.
