Furby was massively popular when it released in 1998. There's dozens of different fur and eye colors, they're palm-sized, and only take four double As. To this day Furby retains a strong following as a nostalgic toy and as an introduction to robotics for many people. Sadly the 1998 version has a glitch where once you turn them on, they will go back to sleep, and to wake them up, you have to press their tongue down and shake them upside-down. It's pretty crazy.