Plasma Ball

The plasma ball — also called a plasma globe or plasma lamp — traces back to Nikola Tesla, who created the effect in the 1890s while experimenting with high-frequency currents in evacuated glass tubes. The modern novelty version was developed nearly a century later by MIT student Bill Parker along with James Falk, who marketed his "Groundstar" design through the 1970s and '80s.

Inside the sphere is a mix of gases — typically neon, krypton, and xenon — energized by a high-voltage electrode at the center, which throws out branching filaments of glowing plasma toward the glass. The magic trick everyone knows: touch the outside, and a single bright tendril snaps to your fingertip and follows it around. There's no sorcery to it — your body is simply a better path to ground than the thin gas, so the energy concentrates wherever you touch.

By the late '80s and through the '90s, the plasma ball was the quintessential novelty-store object — sold at Spencer's Gifts, science-museum gift shops, and mall kiosks, and destined for a teenager's desk or bedroom shelf. (Wikipedia dates its popularity as a novelty specifically to the 1980s, so its heyday genuinely straddles the two decades.) Still sold everywhere today as retro sci-fi decor, it remains shorthand for "cool desk toy" — the thing you couldn't walk past without putting your whole hand on the glass.