People strip down for causes all the time, whether it's for animal rights or the environment. While we appreciate altruistic nudity, it's invigorating to see some good-old-fashioned selfish stripping, like the kind 999 people did in exchange for two free flights from Ireland's Aer Lingus.

Despite a brush with the law that prevented total nudity, the participants made fine use of skimpy shamrocks to cover their more objectionable bits.

The airline recruited the nudes using Facebook and Twitter, and participants allegedly included men and women of all ages, shapes and sizes, although we have yet to notice any of them standing behind the attractive young women.

999 Nudes

    LONDON - MARCH 15: Willing participants remove their clothes for a publicity stunt near Waterloo, on March 15, 2009 in London, England. The airline Aer Lingus advertised on the website 999nudes.com for members of the public to take part. (Photo by Jim Dyson/Getty Images)

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    LONDON - MARCH 15: Hundreds of willing participants remove their clothes for a publicity stunt near Waterloo, on March 15, 2009 in London, England. The airline Aer Lingus advertised on the website 999nudes.com for members of the public to take part. (Photo by Jim Dyson/Getty Images)

    Getty Images

    LONDON - MARCH 15: Hundreds of willing participants sunbathe in front of the London Eye as they remove their clothes for a publicity stunt, on March 15, 2009 in London, England. The airline Aer Lingus advertised on the website 999nudes.com for members of the public to take part. (Photo by Jim Dyson/Getty Images)

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