There are few things as wow-inducing as a high-end car concept.
Real, you-can-buy-them-down-the-local-garage cars are great, but they're usually at least a little bit sensible too. But concepts... why, they can be as kerrrrazy as the designer's imagination.
Nowhere is that more apparent than the Frankfurt motor show. Every year, crowds descend on the city to witness the large German brands do battle in a sweaty hall, and every year we get to gawp at a plethora of shiny supercar concepts.
Here are our favourites from this year's show.
Mercedes-Benz Concept IAA
It may look like an armour-clad armadillo but Mercedes' radical Intelligent Aerodynamic Automobile provides a peek into the future of shape-shifting vehicles. The 279bhp plug-in petrol/electric cruiser features panels that close and extend at speed, meaning the machine slices through the air and uses less fuel when tackling long motorway schleps.
It's just as wacky inside, with a steering wheel that uses Optical Finger Navigation, so the driver can scroll through menus via a sort of touch-screen steering wheel.
It's highly unlikely you'll see one of these pull up at the lights any time soon, but don't be surprised if future Mercedes saloons feature some of the aerodynamic tech seen here.
Porsche Mission E Concept
Elon Musk could be heard gently sobbing into his latte when the silk sheets were dropped on Porsche's latest all-electric offering. Not really - he probably wasn't even in Frankfurt - but the Mission E pure electric sports car has given the Tesla overlord good reason to panic.
It packs the latest lithium ion battery and electric motor tech, which is powerful enough to propel the machine from 0-100 kmph in just 3.5-seconds. But unlike other electric sports car wannabes, Porsche claims its creation can travel for 489 kilometers before the batteries run dry. It's also an absolute stunner to behold and features an interior that's festooned with iPad-esque control screens and fully digital readouts.
Porsche has a reputation for jumping headfirst into innovative ventures, so it's highly likely Tesla's upcoming P90D will have an exquisite German rival in the coming years.
Bugatti Vision GT Concept
As petrolheads across the planet eagerly await the Veyron successor, Bugatti revealed this stunning GT Concept to give them a reason to salivate. It's officially a virtual undertaking for the racing sim franchise but Bugatti wheeled out a full-scale version at Frankfurt to whoops and gasps from the crowd.
A massive W16 engine that pumps an estimated 1500bhp to all four wheels powers it, while engineers claim it could potentially reach speeds in excess of 402 kmph... if they build it.
Don't get too excited: there are no plans to put it into production just yet, but that's not to say the Veyron successor won't steal a few styling tips.