1.Solar panels
Electricity is the defining technology of the modern world. But Western-style power stations and power grids reach only one fifth of Africa. And in many countries the networks are breaking down faster than they grow. Solar panels, by contrast, can deliver power anywhere. In many countries you can see them on the thatched roofs of mud huts hundreds of miles from the nearest power line. A simple roof panel, bought in a village store, can provide enough power to recharge a battery overnight, so families can watch TV and the kids can do their homework after it gets dark.

2.Vacutug
Hundreds of millions of Asians and Africans live in cramped shanty towns with no private toilets or sewers. Public latrines fill up and overflow because conventional pumps that could empty them are too big to get down the narrow alleys. Enter the Vacutug. The invention of Irish waste consultant, Manus Coffey, it was first tried out in Kibera, a slum on the outskirts of Nairobi, where 750,000 people live in an area the size of London's Regent's Park. The contraption looks like a cross between an industrial vacuum cleaner and a motorised lawnmower and can navigate down the narrowest lane. Simple but effective, it is now at work from Dhaka to Hanoi to Dar es Salaam.

3.Condoms
Once, poor people needed children to work in the fields. Now, as they move to the cities and need education if they are to get a job, those children are an economic burden. So everyone wants fewer of them. The number one technology worldwide for cutting family size is the condom. The condom is also essential to prevent the global pandemic of AIDS, which has reduced life expectancy in some African countries by 10 years and left tens of millions of children orphaned.

4.Two wheels
In the rural developing world, the bicycle is a must-have possession for farmers to reach their fields. Even today, more bicycles are made every year than cars. But for the billions of poor city people who can only dream of a car, the essential means of transport to get to work is the motorcycle. From Hanoi to Mumbai and Jakarta to Delhi, they outnumber cars on the streets, and often carry more passengers.

5.Smarter crops
Millions of farmers across Africa are planting weeds to fight crop pests. It sounds bizarre, but weeds round the edge of maize fields are raising yields and fighting poverty. Weeds are free and, unlike the pesticides they replace, don't ruin your health. The weeds are specially chosen. Some attract pests like the stem borer, that would otherwise invade crops. Others release chemicals that kill other more damaging weeds like striga, which takes over fields and wrecks $10 billion worth of maize a year. Such home-grown systems will, say many crop scientists, boost yields and kill pests far more quickly and cheaply than genetically modified crops.

6.Mobile phones and the internet
Landline phone systems have never worked well in developing countries. The state-run companies are hopelessly bureaucratic, and the kit is expensive and always breaking down. Mobile phone systems work much better and are usually just as cheap. Meanwhile, the internet has transformed the exchange of ideas. Even the most dictatorial countries find it hard to filter out dangerous and innovative ideas reaching their citizens on the internet. For grass-roots innovation and democracy alike, this technology is transforming societies.

7.Pepsee
These small tubes made of thin disposable plastic were originally designed to encase individual ice lollipops. They are manufactured all over the world and come in long rolls, to be torn off at perforations. Pepsee is their Indian brand name. Sometime around 1998, somewhere in central India, a farmer discovered that these rolls of tubing made perfect cheap conduits for distributing water to irrigate plants. Now millions of farmers take the rolls, lay them down next to rows of crop plants and pour water in. The water runs down the tubes and drips through the perforations to irrigate the plants. In drought-prone India, Pepsee irrigation uses far less water than conventional flooding of fields, but cost many times less than high-tech drip-irrigation.

8.Television
'Your window on the world', the old slogan for BBC's Panorama, is the literal truth for TV sets in the developing world. Television fights poverty by showing people for the first time how other, richer societies live. Whether it's watching Friends or Who Wants To Be A Millionaire?, the poorest people can see with their own eyes what they are missing.