Imagine a film set gadget looking like a "holoprojector" equipped with a battery-operated LED light. In the movie it is placed on a conference table. The apertures on the side of the holoprojector emit a light onto the table and the actors who are sitting at it. The projection itself will be added later in the post production process.
Other examples: A necklace with a victory medal for Rumpel of the German edition of Sesame Street, a gold record and a fictional magazine cover.
Also in my portfolio: stickers, posters, labels, book covers, concert tickets, school reports, medical records, targets and much more.