DipTrace - DipTrace - Professional Schematic Capture and PCB Design Software
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
KiCad EDA - A Cross Platform and Open Source Electronics Design Automation Suite
Oregano - oregano - An electrical engineering tool for GNOME
Autodesk EAGLE - Autodesk EAGLE is an electronic design automation (EDA) software.
Circuit Simulator - Animated electronic circuit simulator using ideal components to visualize voltage and current.