Apparently, making cars is the third biggest industry in the world, after cocaine and arms.

That's arms, as in guns and missiles, by the way. The global business in arms, as in arms, is extremely small. In fact, I've just looked in the Yellow Pages and there isn't a single shop in all of Oxfordshire that could set me up with a new one.

That said, there is also not a single shop that could set me up with an AK47, even though we keep being told that after a 60-year production run, enough have been made to equip one in six of the world's population.

I'm not sure about that. I've racked my brains all morning and the only person I know who has one is... er... me.

What's more, you can buy an AK these days for as little as $3 - though not in Chipping Norton, where they can be anything up to £300. But even so, you'd struggle to buy a car for that. And it's the same story with cocaine. I don't know how much it costs but unless it's £20,000 a gram - and judging by its popularity among school children these days, I bet it isn't - it would struggle to be a bigger business than cars.

So no. After much extensive research, in my head, and Yellow Pages, I have decided that in fact, the car industry is much bigger than the industry for both kinds of arms, and drugs.

You'd imagine then that such a big business would have ensured in its 100-year history that every single stone had been turned, and every single niche filled. You'd imagine that whatever sort of car you might want, someone, somewhere would be making it. And someone else would be making an alternative that costs slightly less.

This is certainly the case with the mini MPV. Designed exclusively for people who are mentally dead, almost every mainstream car maker in the world is able to sell you such a thing. And there's more. They can even offer you mini MPVs with four-wheel drive. Which means they are making mini MPVs for people who are mentally dead and who want to go to the woods at weekends. In other words, the car business is making motors for mentally dead murderers. And there can't be more than five of those on the whole planet.

Then you have track-based sports cars. I see. And who are they aimed at exactly?

In order for track days to make sense, you have to live in an over-governed police state (Britain) with lots of race tracks (Britain). In other words, there's a only a tiny number of people who want to whizz about in a flurry of noise and expense, but the choice of cars they can use is endless. Porsche alone makes eight.

Small cars? Thousands. Off roaders? We're up to here in them. You even have a choice of downmarket, quasi-British four-door saloons, even though no one has actually bought one since Terry and June went west. Strangely, however, the choice of large, luxury saloon cars is very small.

No. That's not true. They are ten a penny. But though the car industry is huge, and run by people who might want to go home in such a thing, there's something wrong with almost all of them.

King of the hill is the Mercedes S-Class. Laden down with an extraordinary array of gadgets, it's silky smooth, good-looking in a discreet way and, after a period in the quality doldrums, beautifully made as well. It is the obvious choice.