Good EE Software

LTSPICE – Free, Industry Standard Circuit Simulator – Best thing ever

GerbV – Open Source Gerber File Viewer

CircuitMaker – Free, cloud-based PCB Design tool – made by Altium

Altium – The PCB Design tool (industry standard)

Arduino – IDE for Arduino / other Microcontrollers 

Saturn PCB Toolkit – Great tool for EE calculations of all sorts