Theres nothing worse than looking forward to a serving of Nutella on warm toast for breakfast-only to find that someone has cleaned out the jar. But German inventor Daniel Schobloch has come up with a brilliantly simple solution to the pilfering problem-by designing an acrylic[丙烯酸的] lock to keep jars of the chocolate and hazelnut spread safe from sticky fingers.

The canny gadget， which started life as a joke invention， is currently on sale for 9.99 on eBay Germany. The simple lock is so popular that 1，000 units have been sold so far. The acrylic lock means that no one can open the jar without a key， which will stop late night snackers and early morning pilferers in their tracks.

Daniel， who works at Borkenkarger Furniture and Fittings， told Berlin-based The Loca/ that his invention started life as a joke. He said：“One of my friends was always getting worked up because his children were always stealing his Nutella.”But once news of his clever creation got out， the demand for the lock started to spread.“As the demand continued to grow we decided to offer the device on eBay，”he continued.

The lock， which comes with two keys， should not be considered as a proper security device however， as acrylic is easy to break into. Daniel told The Local that the lock is best used as novelty gift or by parents who want to stop their children from gorging on the sweet spread.

Barmy breakfast inventions seem to be all the rage recently with news of a British designers bizarre Wearable Brek range， made especially for cereal fans.

Dominic Wilcoxs creations include a device which sets off an alarm if your cereal is too soggy， a crane that serves milk and cereal into your bowl， a cereal drone that flies Rice Krispies from shop counter to table and an e-Spoon that measures the mouthfuls of food as you eat. The prototypes， commissioned by Kelloggs， were created with the aim of adapting the“wearable tech”trend to revolutionise the way we eat breakfast.