for Arcade DIY fanatics

Arcade-Spinner
A custom Arcade Spinner using standard Fight Stick box & Arduino micro-controller board.
Use on racing games and Pong style games - simulate the steering wheel or paddle/spinner style controllers.
URL: https://craigb-spinner.github.io/Arcade-Spinner/
Video: Spinner in Action

Arcade-Trackball
A custom Arcade Trackball using home-made fabricated box & Arduino micro-controller board.
Use on games that have a big ball (Trackball) to control your movement.
Use standard non-PS/2 Trackball (aka Happ/Atari style) with no-lag interface controller you build.
URL: https://craigb-spinner.github.io/Arcade-Trackball/
Video: Trackball in Action

Dual Arcade Stick
A custom Dual Arcade Stick using home-made fabricated box & two Zero Delay Controller boards. Use on games that have two joysticks to control your movement and directional fire.
URL: https://craigb-spinner.github.io/Arcade-Dual-Stick/

for Atari DIY fanatics

Atari XL/XE function keys - Have You Played ATARI … Today!
The Atari 1200XL introduced four function keys.
Release of 600XL, 800XL, 65XE, and 130XE kept most of ill-fated 1200XL Atari OS which still retained code for function keys.
You can mod your later model ATARIs to add cursor/function keys.