You can with Ajax load an HTML page on the (same) site, extract data from it and display them into the current page. And thanks to Gears, this works offline too.
This demos loads another HTML page, anaa-functions.html, take inside a table that holds the list of Anaa's functions, and stores this table into this page just above the buttons.
See the source code of the script (the part that is specific to this demo).
Once this page is loaded, go offline by a click on the first button. You can now close the Internet connection and load this page again, and click on submit to try the demo without connection.