My brother-in-law and his family were in town over Thanksgiving. He’s a big Superman fanboy so I made him this desk/shelf ornament out of a piece of 3.5x3.5x1" red oak. Reverse engraved both sides and etched his name in Kryptonian on the edges (50%, ~14mA, at 400mm/s). Works out that 3.5" (89mm) is right at the focus point. So I just cut a frame out of 6mm ply to hold the block and glue on some strong magnets to hold the frame steady on the floor of the laser compartment when I etched the edges. Lol he was so blown away 
That came out great ! nice work