#2391: Enfilope

I’ve noticed a tendency, during train journeys, for people to file their nails and then act as if the various dusty fragments simply disappear.

In fact, some of them end up adorning the clothes, not to mention lungs, of their fellow passengers.


Today’s invention is a nailfile attached to the inner face of a small envelope.

When you file your nails, the various scrapings end up in the envelope, which can be discarded (or sealed temporarily and retained for next time).

2390: Printdoor

Having recently been painting a logo on a steel roller blind, today’s invention is particularly appealing.

It is a simple gantry system that moves a lump of chalk backwards and forwards, as the door closes, so as to create dots whose locations can be computer controlled. This draws a detailed but temporary image on the door surface, just like a computer printer.


As the door is opened, this film of dusty dots can all be brushed off, ready for the next cycle.

In this way, ever-changing adverts, logos, -tweets even, can appear on otherwise bland industrial units…at least when the weather is dry.

(Image copyright Danny Gilbert)

#2389: Batterotation

Battery chargers are a bit boring.

Today’s invention is a way to reinject a little extra drama.


Imagine a charger with no LED to indicate when the cells are charged.

Instead, there is a single small motor, fed from the mains and rotating the batteries slowly via a little gear.

When charging is complete, the batteries will have turn from showing eg a red outer side to a uniform green.

It would also be possible to have a message on the underside of the batteries, which would be revealed when they were ready.

#2388: Touchistory

In future, when we are surrounded by domestic and workplace robots, it may be necessary to identify which was the one that made a dent in the car door or dropped that wine glass.

You could attempt to film them continuously or read back location logs for every one of the joints of a humanoid ‘bot, but both these approaches would require enormous amounts of datalogging and storage.


Today’s invention is therefore synthetic ‘fingerprints’ for robots.

These machines would have minute inkjet nozzles embedded within their ‘hands’ and elsewhere on their limbs.

These would react to any contact pressure by squirting a tiny spot of a personalised spray onto the surface in question.

The prints could be applied to surfaces that don’t work for human prints (eg fur) and they might be fluorescent under UV light, so that any errors or accidents could be easily detected and the droid responsible suitably adjusted.

#2387: Wheelean

Today’s invention is a new form of motorcycle wheel.

It consists of several concentric, tyred wheels on the same axle as the main wheel.


Half of these smaller wheels can be driven hydraulically to the right (and the other half left), so as to provide much better support and roadholding when cornering aggressively.

This arrangement could also be used to minimise drag on the straights and fine-tune the front forks’ angular momentum when steering into and out of corners.

#2386: ProductionLiner

Many containers on board ships are actually filled not with whole products but semi-finished parts, half-processed materials and other constituents of complex, worldwide supply chains.

In accordance with the whole just-in-time industrial philosophy, today’s invention is to enable more flexible finishing and assembly operations whilst at sea.


Factory ships are currently used for fish processing of course, but imagine if you could take for example a robotic car manufacturing plant and build a supertanker-sized ship around it.

Containers full of materials, parts, and subsystems would be loaded on at various docks and completed vehicles dropped off in major marketplaces.

The ship would be receiving data feeds about how many of which parts could be purchased when and where, in order to optimise its route in terms of delivery times and fuel usage.( I can imagine a container factory on the high seas).

This would potentially make the manufacturing processes more globalised and lessen the pressure on land use in populated areas.

#2385: HoverNet

A fraction of radio waves get transmitted around the globe not by bouncing off satellites but by line-of site transmission between a large number of microwave towers.

These are both costly to build and maintain as well as being so ugly they need to be disguised as synthetic trees.


Light travels even faster through the air than through glass fibres and so it would be a good idea, when communicating around the world, somehow to lessen the number of towers…to zero.

Today’s invention is to replace the towers by UAVs carrying small receiver/transmitter dishes.

These have several advantages:

If some need to be switched out of the network eg for maintenance or due to wind damage, the grid they form can be engineered to self-organise in realtime to avoid dropping signal.

The UAVs are much cheaper and less environmentally intrusive than the ridiculous faux firs.

The units could be kept hovering almost perpetually by converting a fraction of the microwave energy they receive into propeller work.

Narrow beam-widths make it harder to intercept the signals and, in any event, the UAVs could constantly move through small amplitudes, randomly, in order to frustrate such attempts.

Although rain fade might be a problem, this could perhaps be lessened by locally increasing the numbers of UAVs when a downpour was predicted.

#2384: ConDots

The Gates Foundation recognises the importance of condom use to world health, so my application to them for funding will be based on today’s invention.

I’ve made suggestions before based on Alan Turing’s work on pattern formation.


In order to make men keener to use condoms, they should be patterned with spots (rather than stripes).

The effect of this is an apparent visual size increase, thus greatly incentivising the use of condoms.

I hope the image effectively illustrates this comparison (although the average contrast is not exactly equal in upper and lower images).

(My attempts to use other size illusions, such as Muller-Lyer were less convincing).

#2383: Swardrive

Rather than have fleets of noisy grass cutting machines patrolling golf courses, why not build golf carts with integral mowers?

These could be electrically motorised and thus operate quite quietly.


Every round played would save some money and pollution and the resulting cuttings could be dumped automatically in a pile on the way to the 19th hole.

If a golf club had a wide variety of abilities among its players, then the fairways would be adequately mown over time and the rough too would be greatly improved.

(The greens keeper would still be kept busy, though, with his or her specialist grass cutters).

#2382: Swimonitor

It seems that when children are drowning, they don’t thrash about, but instead they first go silent.

Today’s invention is a life-saving technology which takes advantage of this scary information.


Each child entering a body of water would put on a waterproof collar with a throatmike and a small transmitter embedded.

Each child’s signal would be monitored by a system on dry land.

In the event that a given youngster was substantially less noisy than its own average for say 20 seconds, a light on the collar would illuminate, alerting adults in the vicinity.