In 1922, “Violet Rays” were said to cure pretty much anything that ailed you. This Vi-Rex device plugged into a light socket so users could give themselves home shock-treatments, which would supposedly make you “vital, compelling, and magnetic”. Various recalls and lawsuits erupted throughout the U.S., forcing the FDA to finally prohibit their manufacture. The last batch of Violet Ray products was seized in 1951.
Just Google “light therapy” to find a range of new infrared devices whose claims to prevent everything from aging to anxiety sound pretty darn familiar.
Of course, in these enlightened days, they’re sex toys. :)