When a part has been used and is no longer needed, what do you do with it? Typically you either throw it away, restore it or recycle it somehow.
Make portions of an object that have fulfilled their functions go away (discard by dissolving, evaporating, etc.) or modify these directly during operation.
Use a dissolving capsule for medicine.
Sprinkle water on cornstarch-based packaging and watch it reduce its volume by more than 1000X!
Ice structures: use water ice or carbon dioxide (dry ice) to make a template for a rammed earth structure, such as a temporary dam. Fill with earth, then, let the ice melt or sublime to leave the final structure.
B. Conversely, restore consumable parts of an object directly in operation.
- Self-sharpening lawn mower blades
- Automobile engines that give themselves a “tune up” while running (the ones that say “100,000 miles between tune ups”)