Pierre-André Boissinot

Semio Design

This plugin detects if a visitor is using some old version of Internet Explorer and suggests to upgrade to a recent browser. 
The versions to block can be configured in an admin panel. 
Works for blocking IE6, IE7 and IE8. 
Localisation of the plugin into french.

Stop Oldies

This plugin detects if a visitor is using some old version of Internet Explorer and suggests to upgrade to a recent browser.

lupomontero

This plugin replaces the contents of your site with a message asking your 
visitors to use a better browser if they try to browse your site with Internet 
Explorer 7 or earlier.

No IE

'No IE' blocks visits from Internet Explorer 7 and earlier and displays a nice message with a list of better browsers.

Stop Oldies vs No IE