The great joy that comes from being a web designer is getting to view your new website in a variety of browsers, only to find that each renders the site at varying levels of consistency - namely Internet Explorer 7 and below. This video quick tip will demonstrate the five most popular services and tools for testing a website in a variety of browsers.
Please note that there are multiple applications like this. Choose the one that works best for you. I prefer VMWare Fusion, though admittedly, I don't have a huge amount of experience with the others.