We've identified that full browser caches are the cause of a problem on our extranet. It only affects a small number of our users, but we'd like to alert them to the problem and give them some guidance on how to fix the problem for themselves. We'd like to use a similar system to the one which GMail uses. When it detects that your browser's cache is full, it shows a warning message telling users that their cache is full and that it may cause problems with GMail, along with a link to a Gmail Help page on clearing your browser's cache. Does anyone know if there any resources out there, or examples of how to use JavaScript to detect that the browser's cache is full? Thanks.