One of the engineers at Valve sat down in front of the camera to show off the Steam Controller prototype. The demo unit is missing the touchscreen in the middle of the controller. Four physical buttons are in its place. This is the exact same version that 300 lucky testers will receive when Valve begins beta testing.
The video shows off Portal 2, Civilization V, Counter Strike: Global Offensive, and Papers, Please gameplay using the controller in legacy mode. The most impressive portion of the demo is without a doubt Papers, Please as it is a mouse intensive game that requires an incredible amount of speed and accuracy.