Windows 8 can run two metro apps in the same time. You have already seen it before Windows 8 Developer Preview. In this tutorial I will show you how to display two metro apps using mouse pointer. Also, this is not limited to Metro Apps. You can work on desktop while metro app is running on the side. There are two ways to do this.
You need to open two or more applications to start with.
Summery of the app will appear on the left or right hand side of the current app.
Step 1: Open any metro app or desktop.
Step 2: Move mouse pointer to top of the screen until mouse pointer turn to hand.
Step 3: Left Click, hold it and drag it down. Then move it to left or right till the divider appears. And release the mouse.
Remember these two methods will not work on Start Screen. Here is the video demonstration that will show exactly what need to be done to run two apps in the same time.