As a teacher of photography I love to introduce to my students the pinhole camera-albeit in digital! I think it’s a practical, educational lesson plan with instantaneous image feedback for my students to appreciate in photography. Here in this photo (by Alexis Mutuc) I mounted a body cap onto a Nikon DLSR. The body cap has a small drilled hole in the middle, covered with tin foil. The foil is then pierced with the tiniest pin I own. Students were surprised that an image can be produced without a lens!