20 years ago today, the World Wide Web was first invented by (now Sir) Tim Berners-Lee. The most successful "spin-off" to come from particle physics in recent times, the WWW has transformed one after another the way we inform ourselves, do our shopping, and (with social networking sites becoming the great wave) keep in contact with (or even find) friends.
The reason the web was invented was of course the large-scale collaborative nature of experimental particle physics research, which created a need to connect the various bits and pieces of information that were created by different collaborators into a coherent whole. Other areas of science have become more and more collaborative as well, and researchers in those areas have also profited from the existence of the web, as have countless groups of people inside and outside academia who are connected by some common interest, but separated by geography.
One discipline which so far has withstood the tendency towards large-scale collaboration has been pure mathematics, which is still dominated by single-author papers and sometimes two-person teams. Fields Medalist Tim Gowers has now set out to use the web in order to transform the way mathematical research is (or at least may be) done: on his blog, he has started a series of discussion threads aiming for a new proof of the density Hales-Jewett theorem for k=3 (which apparently is of genuine interest to combinatorialists) by a large-scale collaboration of mathematicians connecting their ideas through the web. This project appears to have succeeded. Whether this is the beginning of a new era of massively-collaborative mathematics remains to be seen, but it is fair to say that the World Wide Web's power to transform many and diverse areas of human endeavor by bringing people and information together in new ways still hasn't found its limits.