Pressure cookers are relatively inexpensive, they're in every kitchen store, your grandma probably had one, but a lot of people don't. A pressure cooker is interesting because by pressurizing the vessel, you're able to cook much hotter than the boiling point of water, and still have water be present.

It's very hard for individual inventors to get paid. For the same reason that private equity is valuable - broadly, that's a good thing - in the case of patents, many that own them aren't in a good position to take the next step.

Making money from enforcing patents is no more wrong than investing in preferred stock.

Nathan Myhrvold Quotes