When it first went on sale, it was a Teutonic vision of the automotive here and now, a car so in tune with the zeitgeist that you needed thick-rimmed, media-type glasses just to look at it.
It hasn't really dated. But, just as the original iPod gave way to the iPod Mini and then the iPod nano, sales targets and stiff competition tend to dictate that times will change.
Now the motoring press are speculating on the imminent arrival of the next generation TT, which leaves Audi with the difficult task of maintaining interest in the current model for as long as possible.
And, given that the new Audi TT is expected to be shown at the 2006 Geneva Auto Show in March next year, Audi have their work cut out.
What we know about the "TT two" is that it's styling is expected to "remain loyal" to the original design penned by Freeman Thomas, with the only significant differences to the headlights and tail-lights adopted from the "Le Mans" concept.
But, if you're the kind of person who doesn't much care whether you have a nano or a Walkman - so long at it looks good and works well - read on.
Keeping the marque alive until next year is the Audi TT Coupé quattro Sport, a car with a long name and a shorter 0 to 60 sprint.
Leaner
Audi's engineers have come up with the genius idea of stripping out as much of the TT's interior fineries in order to create a leaner and meaner posing machine.
Defying the usual conventions of ageing, it means that the TT is getting faster than ever before as it heads gracefully towards obsolescence. But, first things first: when talking about the TT, styling is all important.
Most noticably, the "Sport" version of the TT gets a two-tone colour scheme, a black roof line sitting atop the lighter-coloured body shell.
Like most things new tech, you pay more but get slightly less - hence there are no back seats or stability bar and the spare wheel has been replaced with a tyre mobility system.
The driver and passenger sit in a pair of low-weight, high-class Recarro bucket seats and the overall kerb weight has been reduced by 49kg to 1,416kg.
Why? You wonder. Well, as well as distinctive looks you also get a Boxster-bating coupé, which is all but ready to hit the race track.
That means that the turbo-charged six-speed manual engine is a little bit more noisy but still quite usable.
Recarros
It handles wonderfully, steers with precision and isn't so firm in the suspension stakes that the Recarros wear a hole in your pants.
It feels rigid and fast, like a proper sports car, and yet looks, to all intents and purposes, like a style statement.
Its exclusive, too, with only a few of the 1,000 originally available still on Audi's books.
Bag a second-hand version and you're looking at a surefire future classic.
Maybe I'll change my mind when the new TT hits the streets but, for now at least, the outgoing TT still has a sporting chance.
