In windows 7 Taskbar instance of an application can easily be created by using Win + Number Key. Here number key signifies the position of the Application in the Taskbar.
If you press Windows + 1, it will create a new instance of the first icon in the task bar. In the taskbar Shown here it will open an instance of Internet Explorer while Win+5 open Windows media Player, Win+7 to Windows Live writer and so on.
Now that's when i wish there must be Double digit Keys as well in Keyboard.
"Windows 7 Tips: Create new instance Application Windows 7 Super Taskbar"
Reference : www.WindowsVJ.com