Not too long ago (I’m saying that so I don’t feel old) computers and their peripherals came in one choice of color and 99% of the time that was beige. Over the years, the beige ABS plastic turned yellow and even darker thanks to flame-retardant chemicals.  A discovery from Commodore Amiga enthusiasts in Germany soon spread through the vintage computer community, reaching LifeHacker in 2009. Before and after photos of plastics treated with the hydrogen peroxide solution show startling results. Dubbed Retr0Bright, the formulas and background information are collected on a wiki. I stumbled upon this not in the context of whitening old computers, but looking into how to restore vintage Lego. My husband’s sister sent us her substantial collection of Lego (so large that most of it is still hidden in the garage awaiting good behavior reinforcement opportunities). Some of the white and clear pieces have yellowed over time, and while they are perfectly usable (except for the one I warped in the dishwasher), perhaps we’ll try restoring them to pristine condition one day.