Summer is nearly upon us, which means it’s drop-top time. But before you search the classifieds for a cheap Renault Wind or Micra C+C, may we politely steer you in the direction of something a bit more Top Gear?

We’ve just found one of the most exclusive and unique convertibles on the planet: a Porsche 959 cabriolet.

It’s the only one in the world, and quite a lot to get your head round. So take two minutes to flick through the pics.

As a quick refresher, the Porsche 959 is a car that comfortably resides in the Supercar Hall of Fame.

First born in 1983, it was primarily a race car. But then made into a homologation special - one of those mystical road cars that only exists so that a manufacturer can qualify to enter their race car in a particular series.

The series in question for the 959 was Group B Rallying. But by the time it’d finally been finished, it was a) too heavy compared to the Lancia Delta Integrale, and b) the series had been closed down.

Nonetheless, Porsche had committed to producing the 959 road car to get through the FIA regulations. It did rally in the end: Porsche put it in the Paris-Dakar in 1986, which it promptly failed to finish before going on to claim first, second and sixth the next year.

One of the lucky blighters to get his hands on a brand new 959 road car in 1987 was Porsche racing driver Jürgen Lässig. But, in 1998, he had a sizeable shunt with an unfortunate Audi 80 on the Autobahn damaging the side and roof of his prized supercar.

However, instead of ending up in the bin, German company Auto Becker bought the wreck, fixed it up and ripped its lid off in the process – transforming it into a slightly incongruous, ludicrously-quick convertible.

It was shown at the IAA in Frankfurt before a US collector took a fancy to it, swapping three million Deutschmarks for the one-off.

You may notice the supercab has interchangeable windscreens: a normal screen as well as a Speedster-style variant. However, the original roof was retained (currently being kept in a giant wooden toy box) and can be used as a hardtop.

Thankfully, Auto Becker didn’t chuck out the engine – so the twin turbo 2.9-litre flat six with 444bhp still remains. And thanks to only weighing 1,450kg (primarily through exotic, cutting-edge materials: aluminium, Aramid - a hugely strong synthetic-fibre material - Kevlar composites and Nomex etc), and the fact that the wheels were made from magnesium, the car will still do a 0-62mph time of 3.9 seconds and a blustery top speed of 197mph.

Fancy it? Well, it’s up for sale at Classic Trader (the same people who sold Paul Walkers Fast and Furious 4 Nissan Skyline) for a cool million euros. Are you tempted to smash open that piggy bank for this one?

See the listing here