Well, this is not chant at all, but I just came across a really interesting site, called "Well-Tempered Clavier: analysis, scores, and digital sound."
You need the most recent Shockwave player to view it, but it's worth downloading, I think. Run your cursor over the piano keys or the menu, and the list of fugues from the WTC will start scrolling on the page. Click on one of them, and you can listen to a little snippet of that particular fugue; click "Play Movie" in the little image that pops up, and you can listen to the entire fugue - and watch a visual analysis of what's going on in it as it develops, too. And there is a bit of English analysis included on the page as well. [EDIT: The same person has created a site that does all this for the Goldberg Variations as well - although it does seem to have some errors.]
The choirmaster and I were just gushing over Mr. Bach yesterday - the incredible prolificacy of the man, and the amazing technical genius! - so this does seem a propos to me, in any case. And I do have a Bach label on this blog, after all - and how could anybody not like this site, I ask you? I love the way the web allows (and encourages!) obsessions of this kind, anyway - so, enjoy.