Here are three paperweights decorated with bit maps - see jpg images of the bit maps. They make use of openSCAD's surface command.

Stl files are:

pw_maze.stl - decorated with a maze
pw_womans_face.stl - decorated with a womans face
pw_dancing_couple.stl - decorated with a dancing couple
closure.stl - disc for closing the bottom if adding weight

OpenSCAD code is included.

The weights are hollow (ca 50 cc volume available) so that steel or lead pellets can be used to add additional weight. The closure can be glued to the base.

Bit maps from 30 by 30 to 100 by 100 may be substituted. More information about how to do so is included in the openSCAD code.