Between 2002 to 2007, I recall a huge number of websites put small fonts in the footer says "For best results, view this website at 800 x 600 with Microsoft Internet Explorer 6", it eventually get updated to something like "This website is optimized for IE and a resolution of 1024 x 768"

The text never got updated to IE7, by the time IE8 arrives, everybody seems moved on to Opera, Firefox or Chrome already, so all websites just removed that footer.