There is significant pressure both to create new airports and not to destroy huge acreages of land.

Today’s invention suggests an alternative approach.

A cylindrical tower acts as terminal building. Each section of the cylinder has a large runway platform cantilevered off it. The sections are powered and can rotate to optimise wind direction for landing etc.

This allows large numbers of planes to land and take off simultaneously in different directions, whilst passengers are transported by lifts up and down the inside of the tower.

It would reduce the amount of waiting enormously and thus lower the costs of air transport.

Today’s invention removes the need for crop spraying aircraft.

Instead, wind turbines placed on the edges of fields would each be fitted with a trough at the base.

When the wind is blowing in the right direction across the fields, the turbine turns in the usual way.

As each blade passes through the trough, it scrapes out a small amount of eg powdered insecticide and this is then dispersed, by the turbulent downstream flow, across the crops.

The particulate matter would be retained within the turbulent boundary layer, so that its distribution could be made reasonably uniform.

There is a lot of rather overheated language being used in connection with a small group of nutters who claim to be able to make firearms using 3D, desktop printers.

First, I’d be surprised if even a very high-spec machine is capable of making a single-shot weapon that would work.

Even if that were possible, printing ammunition would be very difficult.

Why would anyone even bother, when you can buy a shotgun for a few dollars in many US states?

Today’s invention is for those who really think that home-printed guns are some kind of serious problem.

Since low-cost ammunition only comes in a very small number of diameters, each printer should contain, as embedded code, a routine which detects the design of a cylinder with one of these dimensions.

This would cause the machine not to accept any such design file for printing…or better yet, create the desired hardware using a slightly smaller diameter, making any kind of ballistic use impossible.

I’ve written before about bikes designed to break the land speed record.

Today’s invention is an alternative outer skin for one such machine.

Rather than worry about making a rigid monocoque, this surface consists of a translucent rubber sheath which is stretched over the bike and rider as shown.

It is held off the wheels by some guards shown in red, so that the best possible combination of small cross section, drag reducing tapering, minimised weight and rider movement is achieved.

The rider can also see enough to be able to steer without needing any windows.

People buy guns primarily for home defence but they often end up being discharged accidentally and injuring the owner’s own family members.

There is also the danger that a burglar, confronted by a firearm, might get control of the weapon and shoot his way out.

Today’s invention is to fit domestic firearms with a small camera running face recognition software. This is now actually very reliable when asked to find the faces of only a small number of individuals.

It would therefore be trained to detect all one’s family members and used to control the safety catch on one’s home gun.

If this device was pointed at any of the designated people, then the safety would remain firmly on, avoiding some possible tragic consequences.