The Steam Controller's troubled trackpads made for a better Steam Deck - The Verge
Xbox Controller Prototype by CNC milling & 3D Printing
Alienware's gaming controller prototype is what Microsoft should've built ages ago | TechRadar
ProtoPie: High-Fidelity Prototyping Tool for Game Design
Engineering Proceedings | Free Full-Text | Gamepad Design for Touch Generation: Evaluation of First-Person Shooter/Third-Person Shooter Game Control and Possibility of Touched-Based Control as Norm
Playstation 4 Prototype Controller Close-Up - YouTube
Xbox One Prototype Controllers : r/xboxone
Make an Assistive Tech Minecraft Controller
UNITHOR - A Brand New Joystick For Retro Computers by UNI-joy — Kickstarter
PS4 prototype controller revealed? - CNET
A Closer Look at the PlayStation 4 Controller Prototype
Sony tried Xbox stick layout on DualShock 4
Valve's Steam controller prototype now looks more like your father's controller (pictures) - CNET
Hands On With Valve's Steam Controller | PCMag
AliExpress Collection ThundeRobot G45 Pro Three-mode Wireless Gamepad Gaming Controller Hall Effect Built-in NFC for Switch - AliExpress
ProtoPie: High-Fidelity Prototyping Tool for Game Design
Valve adds thumbstick to latest Steam controller prototype | Eurogamer.net
Recon Tech Black & Gold PROTOTYPE Xbox One Controller Microsoft 1708 | eBay
This funky-looking controller is at the center of Alienware's prototype home game streaming ecosystem | PC Gamer
Joysticks: Harnessing the Power of Joystick Technology
Found a Chell prototype, and been having fun testing games with it : r/SteamController