Contest suggestion Answered

How about we have a contest to make the worlds most useful thing? The rules could be: 1. Solid shapes only, no hinges or moving part e.g. pen knives can't be submitted. 2. Using only commercialy available materials and tools. Nothing to specialised. 3. As many possible uses should be listed preferably. 4. No existing products can be modified or coped off. Originality please! just a suggestion XD