cK One is a fragrance that was launched by Calvin Klein in 1998.
It's a highly pleasant smell, in my opinion, and has been described as a blend of cardamom, fresh pineapple and papaya with musk and amber. It's one of my favourite ever smells, for what it's worth.
There were two factors that make it fairly significant from a cultural point of view.
The first is that the scent is unisex - this was heavily played up in the accompanying advertising, with the adverts featuring androgynous, semi-dressed young men and women that positively reeked of bisexuality. This is clearly a technique that's clearly not alien to Calvin Klein, and was used to good effect, attuned very closely to the zeitgeist of the late nineties, where waifs and ambiguous sexuality seemed to be hipper-than-hip.
The second significant element, and part of a secondary advertising campaign, was the creation of what can be described as an "email soap opera". Appended to the adverts of five people (Anna, Erika, Robert, Tia and Ian) was an email address, with the domain name cKone.com.
Emailing one of these addresses resulted in you getting emailed on a regular basis from ten characters about their lives and loves.
This was a revolution, in advertising terms, was produced by the advertising consultants Wieden + Kennedy and the emails were created by an author called Colin Dodd, who wrote the messages for around three years, the emails finally ending in 2002 – with a certain feeling of loss from the recipients.
Such a campaign, which has little if anything to do with the product has become more popular over time, as companies see exactly how the Internet can be used as a marketing device, with an product being advertised with no real direct reference to what's being sold, but rather creating an 'aura' around it. The Blair Witch Project is an excellent example, as is the recent 'i love bees' campaign for Halo 2.
The magazine advertising for the two main cK One campaigns can be found at http://www.davidtoc.com/ck/productpix.cfm?Product_ID=1
Wired have a good article on the email campaign ere: http://www.wired.com/news/print/0,1294,50391,00.html