serialport
Node.js package to access serial ports. Linux, OSX and Windows. Welcome your robotic JavaScript overlords. Better yet, program them!
board-io
Provides a standard interface to boards capable of IO (e.g. Arduinos, Maestros, Raspberry Pis, etc) and their firmware
node-pixel
Library for controlling addressable LEDs (such as NeoPixels) from firmata or Johnny Five.
galileo-io
Intel Galileo & Intel Edison IO Plugin for Johnny-Five JavaScript Robotics