This is another great addition to the PowerToys that Microsoft provides for Free. In case you don’t know what happens when you press Alt-Tab, It gives you a list of all your open applications that you can quickly tab thru. Give it a try. Hold down the Alt key then repeatedly press the Tab key. (See the images after the jump)
When you install the Alt-Tab Replacement in addition to seeing the icon of the application window you are switching to, you will also see a preview of the page. This helps particularly when multiple sessions of an application are open.