5. Lexus LF-A
Behold the Lexus LF-A, a supercar that remains a concept car despite being launched in 2005 and contesting this year's Nurburgring 24-Hour race in front of 100,000 fans.
Powered by a mid-mounted 500bhp 5.0-litre V10 engine, the car has a top speed of 200mph. It oozes high-performance styling, too, with much of its body made from aluminium and carbonfibre to save weight.
Even the two radiators to cool the engine are rear-mounted to aid weight distribution. They feed air through ducts just above the rear wheelarches onto a rear spoiler, which is activated at high speed to create more downforce and increase grip.
So will it ever make production? Almost certainly - Lexus has invested a lot of time and money in developing the car to such a high level.
So when will it make production? Well, we've been predicting on sale dates for so long now that we've given up trying.
When's it due? 2006 yes, we hopes to see it two years ago
Chances of 'I Spy' success 10,000,000/1