A CNC laser engraver, however, isn't exactly the cheapest thing around, and you'll be looking at spending at least $150. But ...

(Editor’s note: the old forum doesn’t seem to ... in this point to bring us his red green blue laser. He dug around inside Blu-ray players and DVD drives until he had a collection of lasers ...

In turn, there are now a lot of optical drives sitting unused in parts bins and old computers ... at turning one into a laser microscope. This build requires two DVD pickups.