Acrylic (commonly called Perspex) comes in a wide range of colours and thicknesses. It is suitable for engraving, laser cutting, laser marking, abrasive etching and paint filling. Clear acrylic can be coated with sign vinyl to give an extended colour range.
The main drawback with acrylic is that it has limited flexibility. Care must be taken when handling, fixing and mounting acrylic to ensure it carries low stress and thus will not crack.