For Sale is the Ergotron WorkFit-A, Dual Monitor Workstation with Suspended Keyboard.

This is a height-adjustable workstation that moves your keyboard and monitor in one simple motion, allowing you to change from a sitting to a standing position. This workstation allows the keyboard tray to be positioned below desktop level for user comfort. Additionally, you can fold the keyboard up and swing the arm out of the way when you need the desk surface. In other words, it is completely adjustable to meet your needs.

This is a heavy-duty, high quality piece of equipment. excellent, these cost a little over $700. I absolutely love this thing, but I am currently downsizing and must part with it.