2. Hypercolor T-shirts

Clothing manufacturer Generra created these fad-ready T-shirts in the late '80s, but they really caught on in the '90s. The shirts were dipped in temperature-sensitive pigment, which meant that when heat was applied to the fabric, the color would change. Shirts would turn vague shades of blue, yellow, pink, and gray depending on the level of heat they received, working much like the body-heat activated fad of a previous decade -- the mood ring.