This is a little plugin that performs a smoothing operation on your mesh without adding geometry. This is useful for instance to approximate what subdivision will do to your object while you’re animating without having to add geometry (and thusly achieving higher viewport speeds). It could also be used to smooth out background characters again without adding geometry but maintaining reasonable results.
Usage: Put the .mp in your messiahplugins directory. Add the Smooth effect to your object in Setup mode. Setting of 1 and 1 will smooth quite close to normal subdivision. The last field is for choosing a weight for the smoothing.