We all know just how much “fun” it can be to test for all the different versions of Internet Explorer. Multiple-IE kind of works, but the best solution so far is still using Virtual Machines. Developer Jean-Fabrice Rabaute, the author of DebugBar for IE, has developed a new solution which allows you to compare web sites in different versions of IE side by side. The software is still in alpha, so there are still some issues. Most notably, Flash does not work under IE6; that can be something of a show-stopper for most of our sites. IE6 may still be the anchor that drags our cool applications down into the abyss of compatibility nightmares, but when this tool is ready for prime-time it could really help make IE testing slightly less painful.
Original Ajaxian article: http://ajaxian.com/archives/testing-ie-versions-just-got-a-little-easier