10 Toys So Popular They Incited Violence

Zhu Zhu Pets
A Zhu Zhu pet gets a little grooming during an annual toy fair in 2010 in London. Gareth Cattermole/Getty Images

What's the deal with furry robot toys that they incite so much fervor and zeal? Zhu Zhu Pets caused quite the ruckus during the 2009 holidays when they achieved the coveted "hot toy of the season" reputation. Designed to be unpredictable, adorable and interactive, these tiny robotic hamsters offered a dialed-down version of actual pet ownership.

Zhu Zhu Pets inspired adults to line up overnight for purchase, and caused so many arguments and fights at one Indianapolis-area store that crowd control had to be brought in to restore order [source: Associated Press]. Seriously, living, breathing hamsters cause less trouble than these little guys!