In Ubuntu, whenever you press the middle scroll wheel of the mouse at top of a window, it brings the window immediately behind the current window into focus.
How can this be done in Windows 7?
You can get AutoHotKey from here.
AutoHotKey helps you configure your mouse buttons and keyboard buttons to perform certain script operation that the user specifies. That means the user can code what a specific button press will do.
Here is a tutorial on How to write your own scripts..
If coding is not your thing, there is a package which almost does what you want..