Middle-Click on the Taskbar to Quickly Open and Close Application Windows

Windows 7: Use the middle-click button on your mouse and the taskbar to open a new window for an application or quickly close a window. Here's how.

To open a new window for an application, middle-click on its icon in the taskbar. For example, middle-clicking on the Chrome icon will open a new browser window.

To close a window, middle-click on its Aero Peek thumbnail. This could be useful when you have multiple windows open, since you can quickly close a bunch of them by middle-clicking.

From: http://lifehacker.com/5806706/middle+click-on-the-taskbar-to-quickly-open-and-close-application-windows