While many remember the ’90s and early ’00s as a time filled with grunge music, body glitter and the World Wide Web, those who grew up in the era believe the real icons were NickToons and slime.

If you’re thinking of a gift for mom, you probably can’t go wrong with Nickelodeon’s Gak or Floam, two toys made back in the 1990s. Gak is, as the name suggests, a sloppy sort of slime while floam is ...

I was about eight years old when I received a starfish-shaped plastic container full of squelchy, rubbery, yellow matter. It was utterly baffling. The label simply identified the stuff as “Nickelodeon ...