These were common or garden electric cars, except that their power was generated on-board from hydrogen, their only tailpipe emission was water vapour and their only noise was a faintly-whirring compressor.
How long before we can buy such a car? Some say they're coming to the UK next year. How long until hydrogen is in easy supply? Quite a lot longer. One reason these cars were made available in LA is because the Californian capital has a lot of fuelling stations by world standard - a princely total of 15.
Audi also went on the front foot, design-wise, with its beautiful Prologue concept, claimed to introduce a whole new design style. There's a wider, lower grille, new lights, a new attitude to "muscles" on the sides of the body, an architectural approach to the body lines that design the shape, and a new interior approach.
It was well received, which is just as well. Forthcoming A6, A7 and A8 models are already influenced by this concept - compellingly explained by new design chief Marc Lichte, who was installed after group technical guru Dr Ulrich Hackenburg arrived a year ago to "sort out" Audi's forward models.
Mazda gave us hope of a new leader in the B-segment SUV class with its handsome but confusingly labelled CX-3 (what's a CX-2, then?) and Honda also weighed in with a pretty HR-V for the same sector, hopefully not to be dismissed like its faded predecessor as the Hip Replacement Vehicle.
Jaguar Land Rover always plays well in the US these days - which is probably why senior managers like Ralf Speth and Wolfgang Ziebart were prominently on hand instead of at the competing Guangzhou in China.
They improved their cause with all-wheel drive and manual gearbox versions of the Jaguar F-type sports car, a hugely well-liked car in California, and with the new Land Rover Discovery Sport, also bound to play well with its particularly brilliant styling and five-plus-two seating.
Former Aston design boss Henrik Fisker, who has stepped away from the failed California-based business bearing his name and producing the Karma plug-in hybrid saloon, was on hand with a super-Mustang called Rocket, a 725bhp co-operative project between himself and the world's biggest Ford dealer, inevitably Californian.
The car, hugely muscular, is clad in hand-made carbon fibre panels and tipped to cost around £80,000 in the US.
Playing for big money was the new Bentley Grand Convertible, which reprises the old Azure's aura by being happily powered by the venerable 6.75-litre pushrod V8, updated again.
It was interesting also to see Mercedes-Benz reprising the Maybach name we all thought had been compromised in the remarkably tasteless and unsuccessful luxury saloon the group produced to do battle with the Rolls Phantom, back when that car was new. It spectacularly lost the battle.
Mercedes-Maybach is to become a luxury line, just as Mercedes-AMG is the sporty line, and judging by the general approval afforded to the V12-engined S600, now clearly an S-class variant, it is going to work.
The American marques mostly disappointed us. There wasn't much to see on their stands (Buick looked like a deserted parking lot) and their offerings were mostly updates - four pipes, hood vents and a splitter for the new Caddy ATS-V coupé, for instance, and it's not even a 2015 model.
That all seems to prove that the LA Show's fabled tussle for US supremacy with Detroit's show in January is far from won. In fact, if Motown can field a decent number of interesting American creations in two months' time, it might even have been lost.
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