Rounding out the third of its three major announcements, following SteamOS and Steam Machines, Valve Software has revealed the Steam Controller, its own take on a physical input device, intended to offer game players an interface that aims to offer the strengths of both a keyboard and mouse experience and a conventional console controller.

Traditional gamepads force us to accept compromises. We’ve made it a goal to improve upon the resolution and fidelity of input that’s possible with those devices. The Steam controller offers a new and, we believe, vastly superior control scheme, all while enabling you to play from the comfort of your sofa. Built with high-precision input technologies and focused on low-latency performance, the Steam controller is just what the living-room ordered.

The most prominent new feature of the device are the dual circular trackpads, which take the place of a conventional controller's analogue sticks and promise an input resolution approaching that of a desktop mouse. The trackpads are described as "light touch" devices with high fidelity haptic feedback that will purportedly be much more targeted than traditional rumble motors, and even function as rudimentary speakers.

The other key feature is a touchscreen in the centre of the control, which looks to be similar to that seen in the upcoming PlayStation 4, or the OUYA controller, but appears to be an actual digital display, that can also be overlayed over the game action with Steam integration.

There's a total of sixteen clickable buttons, with the four conventional triggers of the top, and an additional two in the lower finger position on the device's rear.

The Steam controller has been designed to support all past, present and future Steam games, and will offer players the ability to customise every binding on the pad to their preference and share those configurations among the Steam Community.

Valve has also promised that the design will be completely open and hackable, inviting others to contribute, which seems to imply that they'll be publishing full schematics and allowing third partys and general users alike to manufacturer their own versions of the device.

The Steam Controller will be dished out for public beta testing along with the previously announced prototype Steam Machines, with 300 lucky Steam users getting one shipped to their door before the end of 2013 -- although prototype versions as said to include a four button panel in lieu of the touchscreen display, and will be wired, rather than wireless. More details and an in-depth description of each aspect of the device can be found on the announcement page.

Valve has also promised to share more about its design process, and the specifications of its prototype Steam hardware "next week".