Anyone who has ever tried to hang wallpaper or to cut fabric knows that it can be hard to achieve any kind of long, straight edge. If you are working with expensive materials, the cost of having snipped a section which is slightly too short, because of irregularity in the cut edge, can be very high. So you might try using a long ruler and marking the line to follow…but that requires potentially defacing the very item which is soon to be on show.

Today’s invention is a pair of scissors equipped with a small laser beam projector (adapted from those which are commonly used in eg portable CD players).

The laser beam is mounted on the outer face of one of the halves of the shears and, driven by a small pendulum, this ocillates so as to describe a fine, coloured straight line along the surface of the material being sectioned, directly in front of and in line with the scissors.

A more advanced version might take the form of a stationary projector which would form an entire cutting pattern image, showing eg a tailor or a vehicle upholster where the blade should go.

Young dogs seem to chew anything within reach. This is obviously hard to discourage and may even do damage to the animal’s mouth. In particular, they seem to like to gnaw on their bedding and, if not closely supervised, their baskets.

Today’s invention is a puppy basket in a woven construction. The weave is made not of wicker, but of rawhide strips impregnated with a dental disinfectant. Since the animal will soon grow out of both this bad habit and the basket itself, it might as well contribute to the pup’s health.

This being summer, it’s the season for being rained on at barbecues. Since I like my meat actually cooked, rather than ‘rare’, I have to spend a lot of time watching whatever is being made on my behalf. Food in preparation always gets shuffled about on a grill a fair bit, making tracking one’s forthcoming steak much more difficult.

Today’s invention is a dogtag for barbecue items which helps ensure they are cooked to your taste.

On arrival at the cookfest, you would be handed several tags made of a heavier than usual aluminium foil. Each tag has an alphabet pressed into it which allows you to punch holes where your initial letters appear (using eg a wooden skewer, or at a pinch, a pencil).

Having done this, the selected pieces can have a normal bulldog clip attached to their edges and a tag twisted around the ring on each bulldog clip, gripping it securely and allowing it to be identified irrespective of orientation.

Similar punched holes in the tags can be made to express your sauce preferences and to allow the chef to easily determine whether bleu or bien cuit (cindered) is required. The clips can be dishwashed clean afterwards and the tags discarded.

Military helicopters sometimes have to make a forced landing: an event which often results in a sickening impact with the ground and multiple casualties.

Today’s invention is an adaptation of the Russian approach to space vehicle landings, using retro rockets, which attempts to lessen the injuries caused in such helicopters.

In the event of an imminent crash landing, the underwing munitions on board a military helicopter could be swivelled to point vertically upwards (but with the release catches still locked). All such rockets still on board would be automatically and symmetrically fired, when the vehicle was within a few feet of the ground, significantly cushioning its impact.

Now that fuel is at a ridiculous price, criminals need to be deterred from hijacking roadgoing tankers and stealing their contents.

Today’s invention is a simple mechanical keypad lock applied to the outlet valve of a tanker. This would be made extremely attack-resistant and the combination reset daily. Although few crooks would be daft enough to try using a flame cutter to remove it, even using a hammer and chisel might result in a spark and a truly massive explosion.

Filling stations would be replenished in a sequence that would be hard for a small team of external observers to detect. The combination required to open the lock on a particular day would be called, or texted, through to a particular filling station. Similarly, the address of the target station would be called to the tanker driver only after departure. This would make it futile to stop the truck and threaten the driver or to work out which station to visit and threaten the staff to revel the combination.

Buying a fresh bread stick is a great luxury as far as I’m concerned. I know the French often eat theirs en route from the shop, but I like to get mine home in one piece. Given the mechanical properties and geometry of such bread, I rarely manage to arrive chez moi without snapping each loaf into at least two sections.

Today’s invention is therefore a simple protectif-de-pain. It takes the form of a long, thin foil bag, closed at one end. When the bread is inserted into the bag (which can be reused) a small hand-operated air pump (of the kind used to seal a half-consumed bottle of wine) is used to evacuate the bag. This is then knotted tightly and placed on sale in the usual way.

The partial vacuum within the bag allows external air pressure to rigidify the exterior foil skin, rendering it much more nearly impervious to collisions with the inside of the shopping trolley or car boot.

It also retains more moisture (and tasty smell) than any paper bag can, which adds value to the product in excess of the cost of the mass-produced bag.

Everybody would like their laptop battery to last longer.

Today’s invention is one way to allow that. Normally, when left alone for a while, one’s screen will dim. I suggest applying that by default to all screen real estate, apart from the active window. The screen would thus use a great deal less energy, at the expense of a small amount of extra control circuitry/logic.

It might be possible to have different windows with varying levels of local illumination, depending for example on the recency of last usage (although I can’t think why this would be useful, other than for aesthetic marketing reasons when the machine was on display -or perhaps to draw attention to different windows in a particular order).

Misfuelling is the dreadful name given to putting the wrong fuel in your vehicle. Diesel in a petrol car = bad news. This can be a very costly mistake to make and so there are numerous devices to ensure motorists avoid it. The odd thing is that drivers aren’t all buying these and manufacturers aren’t getting their acts together to factory-fit them. Maybe it’s to do with car companies selling anti-misfuelling insurance?

I was irritated therefore when filling my tank recently (already pretty miffed about the price) to find that the nozzles had been swapped in the pump holsters (the hoses always form a hydra-like rope which doesn’t help distinguish between their origins). Whether caused by some malicious miscreant or just a moron, I nearly ended up with 10 gallons of unwanted Extra-Green-Superoctane-Plus, together with an additional £3k bill.

Today’s invention is a simple, colour-coded plastic location device which is fitted to the ‘heel’ of each nozzle and which allows it only to fit into the correspondingly-shaped locator attached to the correct holster.

A ring or bracelet can be given more lasting value by the memories associated with it. That’s why, I suppose, people care so much about the inheritance of family jewellery and why eg watch manufacturers centre their advertising on the idea of passing their (pricey) products on.

Today’s invention is a ring which can add sentimental value to itself.

The ring would have within it a heart rate monitor. This would record the times when the wearer’s heartbeat exceeded a certain level. The ring could then be wired up to eg a mobile phone (without being removed) and request verbal annotation by the wearer of the exciting events of the last day (or week).

Over time, this would build into a personal history of successive generations of wearers.

I’m told that using a look-down viewfinder is very strongly preferred by many photographers. One of the biggest advantages, apparently is that when taking portrait shots, not being looked at by the snapper directly puts a sitter in a more relaxed frame of mind.

Today’s invention is a simple variant on the standard compact camera LCD display back.

In this case, the display faces the rear of the camera and can be hinged outwards to allow a photographer to look down on it and see the scene in the correct orientation. A wider range of hinge rotation might be provided to allow for conventional positioning of the LCD display on the back face of the camera, facing the user.