I'd experimented with the Structured Blogging plugin for WordPress almost 3 years ago. It's a way to add structured, complex data to regular blog posts, and provides both human- and machine-readable versions of the content in order to support aggregation and syndication of the data by any service that supports it. The plugin adds a bunch of extra types of posts, from generic reviews and events, to more specific formats such as Journal Article and Book. Those two formats would be extremely useful to any student (or faculty member) who is collecting notes on academic research for use in their studies.
The Journal Article and Book formats also integrate with services to automatically look up reference data. For example, while writing a review of an article in Nature, all I would have to do is enter the article title and click "Lookup: PubMed" - and the rest of the data was automatically queried and entered into the article review.
Similar features are available for books (via Amazon.com). And some formats also provide star ratings as additional fields, making ranking and reviewing items very simple.
Sure, it could be argued that the implementation is somewhat hackish - it replaces the rich text editor, and stores XML in the post content - but it works. That's really all that matters.
Unfortunately, the Structured Blogging project appears to be defunct. The website has been abandoned, and the WordPress plugin hasn't been updated since March 2007. The WordPress plugin still works, though, but for how long?
Hopefully, the promise of structured blogging and microformats won't be abandoned outright. The decentralized, flexible nature of these complex content types has some really interesting implications on distributed publishing and recontextualization of information. It would be a shame to have that completely disappear.