The diabolically laughing folks at Evil Mad Scientists Laboratories developed a machine that will draw precise patterns on an egg:
The Eggbot has a rigid but adjustable chassis that allows you to mount spherical or egg-shaped objects of various sizes, and rotate them about their axis of symmetry using a stepping motor under computer control. A second stepping motor moves a pen about an axis perpendicular to that "egg" axis, and a small servo motor raises or lowers the pen above the egg surface.
Link via Make