Remember the movie Mad Max with Mel Gibson as Max Rockatansky, a desperado figure who roamed post-apocalyptic wastelands in a battered black vehicle, scavenging for precious petrol to fuel his V8?
Is that the kind of future we can expect for ourselves? Will there be backstreet petrol dealers shiftily offering a gallon of unleaded, no questions asked about where they got it? Will unscrupulous types dilute it with washing-up liquid to maximise their profits?
Because the oil reserves will run low sooner rather than later, but our long love affair with the automobile shows no sign of cooling.
I thought about this at the weekend as an amazing 175,000 people converged on Goodwood to celebrate motorsport and car culture at the world-renowned Festival of Speed.
There may be more and more pressure to cut carbon emissions these days and it costs us a small fortune every time we fill up at the pumps. Tax and insurance keep going up too – but we’re all still driving around.
No government has yet been brave enough to try radical measures to reduce the ever-increasing number of vehicles on our roads because it’s a surefire vote-loser.
But eventually something is going to have to give. Imagine if only certain people who could prove a genuine need were allowed to drive on public roads and the rest were left to the mercies of the public transport system.
Or maybe one day in the not-too-distant future, we’ll all have a personal petrol allowance like food coupons in the war. When it’s gone, that’s it.
Perhaps there’ll come a time when motoring is something we only do at weekends as a hobby, paying to go for a nostalgic drive around a track.
At Goodwood there was an interesting FoS-Tech exhibition giving an insight into car manufacturers’ attempts to harness green power with electric and hybrid vehicles.
But range and cost are an issue and alternative technology has still got a long, long way to go before it can hope to supplant our beloved internal combustion engine.