Five battery-operated robotic hamsters costing about $10 each have become the must-have toy of Christmas 2009, with parents in North America and the UK snapping them up as soon as they arrive on retailers’ shelves.

Zhu Zhu Pets, sold in the UK as Go Go Pets, are the hottest toy of the season, according to Jerry Storch, chief executive of Toys R Us, the retailer, a phenomenon on a par with Teenage Mutant Ninja Turtles, the smash hit of Christmas 1987.