Everyone loves a supercar. They look great, sound great and go like stink - they also stretch the very limits of what all car enthusiasts love about cars.

But not all supercars are success stories. Some are headline-grabbing vapourware, which are wheeled out at motor shows one year and gone without a trace the next. Some actually manage a few sales before the game moves on and everyone forgets them in favour of the newest supercar with more of everything. We're taking a look back at some of these valiant supercars that time forgot.

Cizeta Moroder V16T

Have you ever wondered what a car would look like if it were built by a disgruntled Lamborghini designer and a musician? Then wonder no more.

The Cizeta came from the pen of Marcello Gandini - the man responsible for the Lamborghini Countach and Diablo - and the wallet of Giorgio Moroder, the composer behind the soundtracks for Scarface, the Neverending Story and Top Gun. The real party piece of the car though was the freakish engine.

The car gets its name from the V16 engine mounted sideways - transversely - behind the driver, contributing to the near 7 foot width of this beast. However, just calling it a V16 doesn't do it justice - it's a pair of V8s sharing the same block mounted to the same gearbox that fits in the middle of them, generating a most unique noise. Producing 550hp, the Cizeta could shovel to 204mph despite the colossal kerbweight - no exotic materials were used in the construction, just a moly steel spaceframe and aluminium body panels.

Only eleven of these cars were ever built, though it's seemingly still possible to order one if you have the £650,000 required. And yes, that's four pop-up headlights.

Mercedes-Benz CLK GTR

Back in the late 1990s, the FIA took over GT1 class racing after interest from several major manufacturers - Mercedes, Porsche and McLaren included - and introduced the FIA GT Championship. Part of the ruleset for the championship and, later, the GT1 class at Le Mans required production of road cars on which the race car would be based. Of course McLaren didn't have this issue, with the racer being a detuned road car, but other manufacturers had to produce homologation specials, like the Mercedes-Benz CLK GTR.

After AMG had worked their magic on the race car, developed in just 4 months, production of 25 road cars commenced. Initially powered by an enlarged version of the race car's engine - a 600hp 6.9 litre V12 - the 200mph cars cost purchasers a cool million pounds. Later versions included a 655hp 7.3 litre V12 - the same engine Pagani used in the Zonda - and even a convertible version. After 20 hardtops and six roadsters, production ceased.

With the class shake up in 1999, Mercedes had no further need for the CLK GTR and turned their attention to prototypes - which turned out to be flippin' awful.

Jaguar XJR15

In the late 1980s, when the Jaguar XJR-9 was dominating sportscar racing, Jaguar Sport boss Tom Walkinshaw chose to make a road car based on it. With the project approved by Jaguar and a one-make race series based on the car in the pipeline for 1991, TWR enlisted Peter Stephens - later to design the McLaren F1 - to design and modify the XJR-9.

The resulting car was incredible. With a huge, naturally aspirated, 6.0 V12 hanging out of the back and producing 450hp, the road car could hit 200mph and the three race Jaguar Intercontinental Challenge supported the Formula 1 circus at Silverstone, Monaco and Spa-Francorchamps, with a million dollar prize.

However, the compromise between racer and road car lead to some unusual handling characteristics. The high and heavy V12 behind the driver provoked oversteer on the brakes, while the huge, low torque prompted oversteer on the throttle. The Silverstone race highlighted this particularly, with more than a third of the 16-car field retiring and only six cars finishing the race undamaged despite an experienced field of seasoned sportscar and F1 drivers.

Later developments helped - TWR even developed the car's tub into the reasonably successful Nissan R390 Le Mans prototype - but the reputation for trickiness remained. Even at £600,000 a shot though, the fifty cars were snapped up and the later controversy with the Jaguar XJ220's engine means that if you want a V12-powered 90s Jaguar supercar, there's only one choice.

Bugatti EB110

Fifteen years before the Bugatti Veyron there was another world-beating and technologically complex Bugatti supercar.

The EB110 sported a tiny, 3.5 litre V12, but complemented by four turbos it could kick out up to 600hp. With a full time 4WD system to harness it, the extraordinary EB110 could run to 60mph in just over three seconds and hit 216mph. Unlike most of the other cars here, the Bugatti wasn't a limited run car either - 139 cars were sold, including one to Michael Schumacher. In fact the EB110 only ceased production because Bugatti itself foundered again - having bought Lotus, the brand ran into difficulties due to a recession and was parted out by liquidators in 1995.

The EB110 also formed the basis for the equally (and more fortunately) forgotten B Engineering Edonis - a significantly reworked version of the car with more power and less weight. Though 21 Edonis models were planned, only two prototypes are ever known to have surfaced - which is lucky given how catastrophically ugly they were.

Vector W8

Vector Aeromotive were one of the masters of vapourware. Between being founded in the seventies and the birth of the W8 in 1989, they built precisely two cars - one was a model of "The Vector" for a motor show and the other was a non-running mockup of the Vector W2 - later converted to a running prototype.

In 1989, Vector introduced the W8. A development of the W2 prototype, the W8 used the same carbon/kevlar body materials and an aluminium honeycomb tub as used in group C racers of the day. Looking for all the world like a crashed jet fighter, the W8 packed an incredible punch courtesy of a twin turboed 6.0 V8 racing engine shouting out over 600hp and 600lbft. Vector claimed over 220mph from the car, but testing of the similar but less aerodynamic and less powerful W2 at Bonneville Salt Flats showed speeds in excess of 240mph, five years before anyone but Gordon Murray had even heard of the McLaren F1.

Vector sold just seventeen W8s - one to Andre Agassi - at over £300,000 a pop, yet it represents Vector's best-selling model. Chances are that unless you've seen Cary Tagawa destroying one in the film Rising Sun or played Gran Turismo 2, you'll have never seen one.

Since the success of the W8, Vector's fortunes have gone from bad to worse through various court rooms. Their most recent attempt was yet more vapourware with a 2000hp, 10 litre Vector WX8 mockup shown in 2007.