The ie6-upgrade-warning is a little script (7.9kb) that displays a warning message politely informing the user to upgrade the browser to a newer version (links to newest IE, Firefox, Opera, Safari, Chrome are provided).
The webpage is still visible behind a transparent background, but access to it is prevented. The idea is to force users to upgrade from IE6 and avoid the website from a bad reputation that website is not rendering correctly in IE6.
The script is completely translatable in any language, very easy to set-up (one line of code in webpage and one parametter configuration).
An example of the warning message produced
Installation
Just insert the line
<!--[if lte IE 6]><script src="js/ie6/warning.js"></script><script>window.onload=function(){e("js/ie6/")}</script><![endif]-->
right after the <body> declaration of the webpage and change the e("js/ie6/") to the folder where the script’s icons images are located.
More translations are available over here
Any translations of the script’s initial messages are welcomed.
http://code.google.com/p/ie6-upgrade-warning/
http://www.cssdance.com/simple-ie6-blocker-ie6-alert-using-css/