The bathroom cabinet looks like an old style, but it must be a new one because it doesn't have the razor blade slot.
The razor blades were in the wall, though: O(50) of them. How do I know? It turns out copper pipe can develop pinhole leaks, especially if the plumber was a little careless with the flux.
Drywall cutters look nice and low tech, but they work like a champ on drywall--and on fingers.