Produced in 1996 by the Hog Wild company in the USA, this 'vortex mug' has a built in battery powered stirrer, which enables you to whip up an instant vortex in your drink! Originally marketed as Mr Twister, Hog Wild sell a slightly updated version of this mug, which they now call the 'Moo Mixer Supreme'. As the company point out, the vortex action is good for mixing up both hot and cold drinks. So whether you are mixing up a drink from chocolate powder, or maybe blending syrup and water, it should encourage youngsters to finish their drink.