Instead of throwing away the shells, they can also be reused as a cleaning tool; for example for stainless steel surfaces such as the sink. Simply rub the wet side of the bowl on the surface or a specific dirty spot. Then let it take effect, rinse and wipe dry. The sink is already clean!
The ceramic hob can also be cleaned with potato skins. With the wet side you can rub the whole field or a dirty spot. Then add some vinegar and rub it in. Then wipe dry. You’ll have a clean kitchen again in no time.