Stopette - Zap. You don't smell.

In 1951, lasers were a young science, which makes it all the more surprising that the Jules Monteneir company developed, in that year, the first deodorant applied by laser.

Initially, it seemed like the most obvious application of the technology, since a lasing medium can be created in a number of ways, including by gas and chemical means. It seemed to the researchers at Jules Monteneir that it would be simple to use part of the chemical ingredients in the deodorant product as a gain medium. Then, by means of a small pump laser and it's power supply, carried in an easily portable wagon connected by a thin umbilicus of cables and hoses, the light was channeled through a surprisingly clever (for the time) miniaturized combined optical cavity and beam splitter, housed in the nozzle of the plastic bottle.

Like modern color laser printers, the deodorant product was applied like toner, and due to the accuracy of the lasers, reproducability of an exact underarm spray pattern was nearly flawless from morning to morning... so long as the user mounted the bottle gently in a small bench vise.

However, accidents occurred due to customer error. Many women preferred to hold the bottle in their hand like ordinary deodorant. This upset the delicate components in the mechanism. The lasing medium  could become contaminated by deuterium gas from the deodorant product, creating a deuterium fluoride laser, instead of the intended - and safer - hydrogen fluoride laser. Injuries ranged from second degree dermal burns to accidental amputation.

The landmark case of Rogers vs. Jules Monteneir brought a sudden end to the company's dream of laser-applied cosmetics. In the accident, a customer lost her right arm and brought down a Cessna 190 airplane before emergency crews could get her deodorant to shut off. The resulting settlement brought a string of similar lawsuits, and the company folded in the fall of 1952 under the financial burned of the legal fees.

The remaining stock of Stopette deodorant was sold off to private laboratories as well as the U.S. Navy, where the deodorant applicators were slightly detuned and found new life stripping paint from warships. One such ship was the USS Juneau, which was instrumental in a few of the naval battles during the Korean war, including the sinking of a North Korean ammunition ship at Inchon. One of the crew was quoted as joking "Poof! There goes ammunition!"

The cosmetics industry learned a lesson from the failure of Stopette laser-applied products, and to this day, high energy cosmetics science courses at major universities still suffer low enrollment.