I feel like a have a big interest in different forms of computer and game input, but it's all kinda nebulous and I need to write it down and collect it somewhere.

Particularly on the PC, there were some interesting controller concepts when 3-D games started becoming popular.

• Microsoft SideWinder Dual Strike
• Microsoft SideWinder Freestyle Pro

Use some variety of weight sensors to measure how a person is standing on it.

• 1982 - Joy Board
• 1987 - Roll & Rocker
• 2007 - Wii Balance Board

• DB9 → USB
  9-pin, analogue connector used in lots of early consoles (with unique controllers): Fairchild Channel F, Intellivision, Colecovision, Ataris …
  • Retronic: https://www.retronicdesign.com/en/store/
  • Ultimate PC Interface: https://intellivision.us/intvgames/interface/interface.php

• Gamepad Tester - Browser-based tool for testing controllers.