The percolation problem describes the statistical properties of a lattice from which a fraction p of the bonds has been removed at random.   There is a critical value p_c such that there is long ranged connectedness for p > p_c and only finite sized clusters for p < p_c.    The percolation problem and its generalization, the percolation conduction problem, have phenomenology similar to "classical" critical phenomena, even though they are not described by thermodynamics.   I'll explain the connections, and go on to show how the resistance from an internal point to the boundary of a square  containing a percolating network at p_c can be explained using ideas from critical phenomena and conformal field theory.