Parmigiano Reggiano cheese is a highly valued and tightly controlled commodity. This instructional video shows how to use specialized Parmesan cheese knives to cut the cheese by hand.
It's so satisfying when the fissure opens up and it breaks into the big rough chunks. Bonus: Some places leave the rind intact and use it as a bowl for tossing hot pasta:
• Parmigiano Reggiano: The art of cutting by hand (YouTube / onlyparmesan)