If you have multiple windows of the same program open on your Windows 7 desktop, you can go through or shuffle through them easily in Windows 7.
Shuffle through program windows
Starting with Windows Vista, pressing the Win+Tab key lets you scroll or cycle through all the open windows on your desktop. This is the Flip 3D feature. You can do so in Windows 7 too.
In Windows 7, press down CTRL key and then continue to click on the programs taskbar icon. You will see that you can shuffle through its open windows.
To get a hang of it, open 4-5 windows, of say Notepad, and position them in different places and have some maximized and some minimized, and then try it out.
Once you get used to it, you will find that it is quite a handy feature.
Press WinKey+Tab and see what happens in Windows 8. Flip 3D too is gone. Keeping pace with the times and the Metro UI, you now have a Metro or Modern UI Switcher which gets activated.