My favorite kitchen gadget as a metaphor? That might be stretching it a bit, but hear me out. The favorite kitchen gadget in my house is a garlic peeler. Just pop a garlic clove inside the nondescript rubber tube, roll it back and forth on a hard surface, and the garlic clove comes out with its skin removed or very loose.
In my mind, it is perfect in its functionality, effectiveness, efficiency and low cost. I may have paid around five dollars for it 15 years ago and it looks as good now as it did then, and I wash it in the dishwasher. Newer versions of the same design are about the same price and more colorful since they are made from silicone.
This same functionality, effectiveness, efficiency and low cost is what I strive for when developing new processes or engaging in process improvement exercises. Granted, job functions along with systems and their surrounding processes have many layers of complexity, but the goal should be to create an end product that is as simple and as elegant as possible.