Flip3D was a fun and cool looking feature in Windows Vista that can be very useful for switching between windows. With the improved Windows 7 taskbar, Flip3D was replaced with improved thumbnails and Aero Peek. Those are both good alternatives but I like the speed of viewing all my open windows at once and switching with just two clicks.
This article will show you how to create a Flip3D icon on the Windows 7 taskbar:

• Right click on the Desktop and select New and then Shortcut.
• Type in RunDll32 DwmApi #105 in the location box and click Next.

• Type in Flip3D as the Name and click Finish.
• You will now have an shortcut on the desktop that will launch Flip3D but it has the wrong icon. Right click on the Flip3D shortcut and select Properties.

• On the Shortcut tab click the Change Icon button. 
• Change the Look for icons in this file text box to C:\windows\explorer.exe and it Enter.  The Flip3D icon will now be available. Select it and click OK.

• Click OK to close out the shortcut properties window. 
• Finally, just drag and drop the new shortcut on the Windows 7 taskbar to pin it.