Slashdot pointed me today to some information about the new HTML 5 standard. Specifically, that said standard is going to include a bunch of new semantic tags! You'll be able to mark up times in a machine-readable format; do all sorts of fancy stuff with numeric data; and indicate which parts of a page are navigation, which are the article, which are figures, etc.
Thinking of all of the spiffy search engine options that could be built to draw on these new tags is left as an exercise to the reader. Personally, I'm looking forward to be able to search for text just inside of a [figure] tag. I'm forever half-remembering some really spiffy chart or other graphic that I saw somewhere and not being able to find it again. (I'm both a visual person and a data/statistics geek. What can I say?)
8/23 -- edited to fix the fact that the word "[figure]" didn't display.