Gaining attention lately is the idea of purple numbers -- a way for Web-page authors to make each individual paragraph on every page throughout their sites directly linkable. The idea is that each paragraph has a distinct URL and, thus, can be cited directly.
Influential technologist Tim Bray first tossed around the idea last week; then Simon Willison followed up with a somewhat elegant solution to the problem of how to display the paragraph-level hooks to which people should link; Mark Pilgrim took the idea to its logical extreme; and Chris Dent compiled a bunch of links to various people's comments. Already a few weblogs have implemented the paragraph-level linking scheme, using purple-pound-sign links as hooks after each graf.
I don't plan to implement purple numbers on this site yet, if ever, mainly because I'd rather not litter my pages with distracting post-paragraph links (initially visible or not), but I point it out because it's an interesting idea news-site maintainers should know about. Would there be value in being able to link directly to a particular paragraph in a Washington Post story -- say, a telling quote or a provocative fact? Probably. Would it be worth it if, in the process, it confused millions of people who didn't know why they'd started to see purple pound signs all over the place? Probably not.