I talk about 500 megapixel sensors, diffraction, and the new Kodak 50 megapixel sensor.

Depth of field brackets on cameras are quite handy to start a discussion about picking the right aperture to get a desired depth of field and suggest the concept of the hyperfocal distance. I wish more lenses had them. I've got an old Vivitar Series One lens that has a quite pleasant set of depth of field brackets that work at any zoom length. Modern zoom lenses don't even try to get this right.