Pspice - OrCAD PSpice technology provides the best, high-performance circuit simulation to analyze and refine your circuits, components, and parameters before committing to layout and fabrication
Digital - A simulator for digital circuits.
Solve Elec - Solve Elec is a free educational program to draw and analyze electrical circuits.
LTspice - LTspice® is a high performance SPICE simulation software, schematic capture and waveform viewer with enhancements and models for easing the simulation of analog circuits.
Oregano - oregano - An electrical engineering tool for GNOME
BOOLR - Open-source digital logic simulator