Today is the first day of the race. For 23 days, cyclists will face one of the greatest challenges in sport. Agence France-Presse provides live coverage online in multiple languages through a very deep database-driven Flash application.

You can see it through the New York Times Web site -- linked from a sports special page -- or through ESPN, which has it linked from their home page, and also from a specials page.

The app is impressive even when it's not live, but try to experience it during the final 1 or 2 km of one of the mountain stages later in the race -- it's very cool.