Mug with a hidden penguin

While the mug is full, the design stays out of sight. Only as the drink goes down does the penguin come through, and that small moment repeats with every refill. It turns an ordinary cup of coffee into something with a punchline. In daily use that means you reach for it like any other mug, and the joke comes along free of charge each morning.

The mug measures 8.5 x 13.5 x 10 cm in length, width and height, with the handle counted in the width. The manufacturer gives the material as 100% dolomite, a ceramic material widely used for tableware, and states that the mug is food safe according to the manufacturer, so it is intended for food and drink. No figure is given for the capacity.

• Surprise design inside the cup: a penguin
• Colour: blue
• Dimensions: 8.5 x 13.5 x 10 cm including the handle
• 100% dolomite according to the manufacturer
• Food safe according to the manufacturer
• Part of the Surprise mug series

The mug is made for penguin fans, animal lovers and anyone who enjoys springing a small joke on the people around them. As a present it works for birthdays, Christmas, Secret Santa and as an office gift, where it tends to become a talking point during the coffee break.

Because it gets used every day rather than sitting on a shelf, it stays in mind far longer than most novelty items. Anyone who already owns a mug from the Surprise series will be glad of a second animal to go with it, such as the one hiding an elephant.

When you hand it over as a gift, resist explaining the trick: give the mug, pour the first drink and let the surprise do its own work. The reaction is half the fun. For a larger present, fill the mug first with coffee beans, tea bags or chocolates and wrap the whole thing in tissue paper.

At work it does its best job as someone's regular coffee-break mug, because colleagues then find the penguin on their own sooner or later. And if you are buying for the same person across several occasions, the mug with the hidden elephant is the obvious follow-up to the penguin.

Where is the penguin hidden? The design sits inside the cup. While the mug is full it stays covered, and the penguin appears as you drink.

How big is the mug? The manufacturer gives the dimensions as 8.5 x 13.5 x 10 cm in length, width and height, with the handle included in the width.

What is the mug made from? It is 100% dolomite according to the manufacturer.

Is the mug suitable for drinks? Yes, it is food safe according to the manufacturer and therefore intended for use with food and drink.

Does it work as a gift? Yes, it suits birthdays, Christmas, Secret Santa and small office presents for animal lovers.