History is replete with financial frenzies that seem ridiculous in hindsight, but were viewed as anything but at the time.
The advent of radio technology fostered a dotcom-style boom in the roaring '20s. The biggest example: Radio Corp. of America. RCA's shares soared from $1 to $573 between 1921 and 1929. The stock then fell more than 95%.
NEXT: 1959: Electronics