The properties of polymers at surfaces and interfaces play an important role in a number of applications in technology (protective coatings, adhesives, lubricants, etc.) and biology (adsorption of biopolymers at cell membranes, etc.) and pose many challenging scientific problems [1–5]. There is an interesting interplay between bulk and surface properties in the interfacial regions between the bulk of a polymer film and the adsorbing substrate on one side, and the polymer solution (or air, respectively) on the other side of the film. A flexible polymer chain experiences a loss of configurational entropy near a wall but this may be outweighed by enthalpic gains due to the wall-monomer interactions. While the static aspects of this behavior have been studied for a long time [2–4], using various experimental and theoretical techniques, the dynamic properties of polymers adsorbed on surfaces are less well understood [5–9]. Thus chains, which are partially adsorbed to the walls and mutually entangled, are very hard to treat by analytical methods, but also they are not easy to study experimentally, since the extent to which polymer films are in thermal equilibrium is rather uncertain [5,10].