This is certainly not about Bill Gates' damn screensaver, in fact it is not about computers at all.
Recording the highest pre-order numbers ever, Boeing have just released their new "Dreamliner". It does not look like a revolution in design, but it is expected to be lighter, faster, safer and more economical than current planes.
The first modern jet airliner was the De Havilland Comet, and every structural engineer today knows that they crashed "because they had square windows". Probably not the full reason, but the tiny cracks of metal fatigue were initiated and exaggerated around the window corners where the sheet metal had been cut. Basic science. That is why modern planes tend to have rounded windows.
But even circular windows are not ideal. Obviously the pilot should have good all-round visibility, but the many windows down the side of an airliner are a major inconvenience for the aircraft designer. An aircraft wall with windows is much heavier than an equivalent one without. It would be cheaper to build and cheaper to fly. An airliner without side windows would also, remember the Comet, be less prone to structural failure and therefore safer too.
On the ground where we spend most of our time, natural conditions are a good thing. Broadly, we should be more in tune with our local environments. Maximising natural light and minimising energy consumption are fine goals for your home. However when flying through the air at hundreds of miles per hour in a giant metal tube burning gallons of fuel every second, then a little extra power to light inside the plane is insignificant. And we have already said the plane would be less heavy thus more efficient anyway.
When we travel long haul, our body clocks are invariably disrupted. Jet lag is not pleasant. During a long east-west flight, day and night lose their meaning, or at least become severely distorted.
It would be good if the lighting in the plane could help us to compensate for that. Imagine, the whole ceiling of the plane could be a uniform grey as it leaves the UK and gradually become a bright blue as we near the tropics.
With fewer windows, we wouldn't have people with blinds open with searing sunlight spoiling our inflight movies.
And we would have cheaper, safer air travel.