The 10 best one-off cars ever

Ferrari Pinin

You can picture the Ferrari Pinin loaded with Mafiosi dripping with weaponry, its sharp lines perfectly matching the cut of its occupants' suits. With an egg grater grille and four doors, it would look unlike any other Ferrari, even without Pininfarina's dusting of magic. The car was a 50th anniversary present to Pininfarina, named after the company's founder, Battista' Pinin' Farina.  

While there's only one of them, it's hard not to feel we were all given the Pinin. Its huge snout hides the flat-12 from the Testarossa mated to a quad exhaust that pokes out menacingly from below the rear bumper. You also got a five-speed manual gearbox mounted on the transaxle. We'd like to think the Ferrari's long wheelbase is delightfully progressive in bends, but we can't say for sure as there's only one of them.

BMW E36 M3 GTR Strassenversion

BMW's not short of M3 ones-offs; there's the E30 M3 pickup truck, E46 M3 Touring, and E93 M3 pickup, and the E36 M3 GTR Strassenversion is another rather extreme example. A one-of-one car, the Strassenversion – or Street Version – was built so that BMW could compete in the German ADAC GT Cup.

That being said, the E36's motorsport ambitions weren't exactly hidden. It had colossal wheel arch extensions, a body kit that looked very sporty, and a rather large wing at the back. Power comes from a tuned version of the M3's S50 straight-six, producing around 300PS (220kW), while the E36 gets a seam-welded body and is stripped of almost all weight – be that sound deadening or any electrical luxury – slashing 160kg from the standard M3. The result was a 165mph missile that we're unsure still exists. 

Aston Martin Cygnet V8

Everyone knows that putting a huge engine in a Pee-wee of a car is a fast track to motoring hilarity. We saw it in cars like the 5.5-litre Mercedes SLK 55 AMG and the Renaultsport Clio V6, but the mighty Aston Martin Cygnet V8 makes them slightly underwhelming.

Strapping a 4.7-litre V8 under the bonnet of its Cygnet city car – a rebadged Toyota IQ with an expensive leather interior – Aston built a car you won't find anywhere else. Once you get over the monumental pitch as the Aston squats back on its suspension, the Cygnet is not terrible to drive, with its vast track giving plenty of grip and a limpet-like appearance. We'll forever feel wronged that Aston only ever built one of these cars.

Lotec Mercedes C1000

The Lotec C1000 is what you buy when rare isn't enough; your car must be unlike anything else on the road. That was the problem faced by a wealthy oil sheikh from the United Arab Emirates, who promptly went to Mercedes for an answer.

And the Lotec C1000 was the answer. Lotec was seen as the ideal partner; the company was set up by Kurt Lotterschmid, an endurance racer famed for producing performance upgrades for Mercedes-Benz, Ferrari and Porsche road cars. With his support, Mercedes built a carbon fibre supercar that tipped the scales at just 1,080kg but was powered by a mid-mounted twin-turbocharged 5.6-litre Mercedes-Benz V8, based on the engine in the Sauber C9 Le Mans sports prototype. Performance was never in doubt, the 999PS (734kW) Mercedes getting from 0-62mph in just 3.2 seconds, 0-124mph in 8 seconds, and was reputedly capable of 268mph top speed.

Alfa Romeo Giulia SWB Zagato

Alfa Romeos can be complex cars to love, stunning looking but too often let down by mechanicals that can't cash the cheque written by the beautiful styling on the surface – we point you to cars like the Alfa Romeo 4C, the Alfa Romeo 8C and just about every front-wheel drive Alfa of the 2010s. 

The Giulia SWB Zagato hasn't got that problem because, under its sculpted metalwork, you'll find the 2.9-litre twin-turbocharged V6 and rear-wheel-drive chassis from the Giulia Quadrifolglio – one of the best-driving cars its produced in more than a century of car building. But the Zagato styling is the point of interest here, turning the Giulia into a stunning sportscar that's a modern-day take on the SZ coupes from 1950. 

Bentley Hunaudières

It was 1999, and Volkswagen had just bought Bentley. Keen to show off its latest acquisition, Volkswagen built the Bentley Hunaudières to mark the celebrations at that year's Geneva Motor Show. The Hunaudières takes its name from the Hunaudières straight at the Circuit de la Sarthe, where Bentley had a winning reputation from competing in the Le Mans 24hr.

Strangely, it's not s Bentley that owes the Hunaudières a debt of gratitude. Rather, it's Bugatti because the Hunaudières was the forerunner to the Veyron with a W16 motor and a top speed of well over 200mph. Even the Hunaudières interior is a carbon copy of the one you'll find in Bugatti's generation-defining supercar.

Lotus Esprit Wet Nellie

The Lotus Esprit was already one of the coolest cars of the 1970s even before it got the Bond factor in The Spy That Loved Me.  Having dispatched a motorbike with an explosive sidecar and a pack of gun-toting hoods in a Ford  Taunus, Bond faced his toughest test yet – a helicopter with two heavy machines mounted on the front.  But Bond had a trick up his sleeve; driving off the quayside, his Lotus Esprit turned into a submarine with surface-to-air missiles that could take out helicopter gunships without even needing to surface. 

Having seen off several aquatic threats – from divers to mini submersibles - using everything from torpedoes to mines, Bond served up one of the greatest automotive moments in cinema, his Lotus emerging out of the sea and driving past a beach load of holidaymakers. The car  – nicknamed Wet Nelly – sold for more than £600,000 at auction in 2013. 

Jaguar C-X75

The Jaguar C-X75 was another Bond car only in it all the gadgets fitted as standard. The concept car was powered by two gas turbines that produced electricity to drive the car's four electric motors – one on each wheel. Described as a design study that would influence future models, the C-X75 never saw the light of day, and neither did 250 proposed production models, which swapped the gas turbines for a conventional petrol engine. 

The seven C-X75s that do exist are leftovers from the filming of Spectre, and none of them are road-legal. Until now, after buying one of the cars at auction, an owner commissioned former Jaguar designer Ian Callum to convert one car for road use. 

Pagani Huayra Epitome

With a price tag of well over £2 million, the standard Pagani Huayra may as well be a one-off car to most of us, but if you have the budget to spend, you could commission a car like the Huayra Epitome – which is a genuine one-of-one car, built because one of Mr Pagani's well-heeled clients wanted a more analogue experience than the standard Huayra offers. 

The Epitome is powered by a twin-turbocharged V12 that produces 864PS (635kW) and gets a new suspension setup, including a Ferrari-aping rough road mode that should filter out bumps at speeds of up to 93mph. But the coolest part of the Epitome is its seven-speed, Xtrac-made manual Gearbox that serves power through a triple clutch, motorsport-derived drive shafts and an electronically controlled limited-slip differential. The six-way titanium exhaust seals the deal with this exceptional car. 

Volkswagen Golf GTI W12-650 

The Aston Martin Cygnet V8 already takes the idea of a small car with a big engine to extremes, but the Golf GTI W12-650 goes even further. Looking like a Golf R fed on a diet of steroids and protein, the W12-650 is a Volkswagen Golf with a mid-mounted Bentley W12 where you would expect to see back seats. It took a company like VW to build this parts-bin car. The W12-650 took its Gearbox from the Volkswagen Phaeton, its front brakes from the Audi RS4 and its rear brakes and axle from the Lamborghini Gallardo, all mounted to the body of a Golf. 

With a 200mph top speed, the Golf is undoubtedly quick, but as an underdeveloped show car, it could also be terrifying; reviewers reported a car that could snap into an oversteer at a moment's notice. Nevertheless, cool one-offs don't get much cooler.

So that’s our list of the coolest one-offs. Commisoratory shout-outs (following pressure from colleagues) to the Aston Martin Victor, Ferrari SP275, Bugatti Chiron Profileé and Ferrari P4/5. What's your favourite? Are there any you think we missed? Let us know...