The title, a great one if a little misleading, has been taken directly from the Economist article .
The problem with condom use, particularly in sub-Saharan Africa, is that there is often resistance to using one. The idea behind this new research is to provide women with a method of preventing infection that doesn't have to be used immediately before sex, perhaps just once a day.
The research is in its very early stages but has considerable promise. A water-based gel has been developed which changes state from a solid at body temperature and in an acidic environment, such as a vagina, into a liquid when in contact with an alkaline substance, such as semen. It is however liquid at room temperature so a liquid as it is applied which turns to a solid in the vagina, and then, when intercourse takes place, it re-liquefies and releases microbicides held within the structure.
It could take five years before it is ready to be tested in humans, and ten before its use is widespread.
The University of Utah press release gives more detail, and it is also written up in the Scientific American.