You can make interactive desktop background games with this asset, you can also develop games that sit on top of other games while having access to full functionality of Unity.

There are two modes of function, in the 'bottom' mode your game will display just above the desktop and have a transparent background, this produces the effect of having the game play on the desktop wallpaper layer.

On 'top' mode, your game will display on top of any running windows application or game and have a transparent background, this appears as having an overlay to any existing application or game that is currently running.