By law, you have the right to register as yours the look or aesthetics of an article, provided these are new and distinctive. This is done by registering it as a design, under the Designs Act.
In Australia, exclusivity from registration can be yours for 10 years. Most other countries provide a longer term.
If the article would perform a useful function irrespective of its shape or outward appearance, then it may be better protected by a patent. This is because a design is limited to appearance. If a competitor makes an article that functions in the same way as yours, but has a different shape, you would not be able to stop them, as they would not be infringing your registered design. But if you have protected its functionality with a patent, you may be able to rely on it instead.
Therefore, registering a design is a good way of protecting a fancy shape that competitors will want to copy, but a patent will protect the concept of operation.