Mental Ray has a shader called “round corners”, and lightwave has one called “edge” that both do the same thing. They will take hard edges on a model and (by using normal mapping) give the appearance that the edges are beveled at render time. Usually this can be combined with a regular normal map, and the amount of bevel can be adjusted.
This is a hugely useful shader, as it can reduce the amount of geometry needed on complex models, and cuts back on modeling time. Incredibly useful on imported complex models from solidworks or something similar.
Does cycles have anything like this?