Before long, the soft-drink behemoths, Coca-Cola and PepsiCo, clambered aboard the alternative-beverage bandwagon, introducing myriad non-traditional products backed by hefty advertising, marketing and promotional budgets.
Now, though, what some Americans call "soda or "pop", depending on which part of the country they guzzle it in, is regaining its fizz. Partly it's because soft drinks still remain more readily available than their unconventional counterparts in places frequented by mobile Americans, from movie theatres to sports stadiums to convenience stores.
The other reason for the revival is a decision by Coca-Cola, PepsiCo and even competitors, such as Cadbury Schweppes, to try again to bring "news to the category in the form of line extensions and innovative variations.
And talk about your rainbow coalition: colours of various hues figure in practically every launch.
PepsiCo, which hit a home run last year with a cherry-flavoured variety of its Mountain Dew soft drink called Code Red, brought out Pepsi Twist and Diet Pepsi Twist, both flavoured with lemon, and will greet the summer with Pepsi Blue, a berry-flavoured version of its flagship cola that cleverly reinforces the trademark Pepsi brand colour.
A PepsiCo sibling, SoBe, which specialises in non-carbonated drinks, is coming out with its first carbonated product, Mr. Green. Oh, yes, a diet version of Code Red went on sale last month.
Coca-Cola, fresh from the successful introduction of a lemon-flavoured Diet Coke, is launching Vanilla Coke, labelled in shades of beige and white. There's speculation that a different variety of Sprite, the lemon and lime soft drink, is on the way, but no word yet on which colour it may appropriate.
Cadbury Schweppes, not to be left out, is going the red route, too, with Red Fusion, a fruit-flavoured, neon red companion to the cola-coloured Dr Pepper.
Will Red Fusion and its ilk cause consumer confusion? It's a risk the cola warriors feel compelled to take, because to stand still may be to stagnate. Sales of all soft drinks rose by a minuscule 0.6 per cent last year, compared with 2000, while sales for the two biggest colas, Coke and Pepsi, actually fell, by 2 and 3 per cent, respectively.
By contrast, according to a report from Bill Pecoriello, an analyst at Morgan Stanley Dean Witter, the soft-drink category enjoyed volume growth of 2.8 per cent during the four weeks ending 21 April, the most recent period for which data was available from the market research company IRI - and the colourful new offerings contributed substantially to those gains.
For now, the cola colour wars mean big bucks for Omnicom's BBDO, Interpublic's Martin Agency, WPP's Young & Rubicam and others, all creating campaigns for the newcomers. If they should falter and soft drinks resume their hard fall, fear not, Madison Avenue: Coca-Cola is rumoured to be feverishly concocting a dairy drink named Choglit, which from its name alone sounds as if a huge ad budget will be needed to put it over.