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.

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

QUCS - Qucs, briefly for Quite Universal Circuit Simulator, is an integrated circuit simulator which means you are able to setup a circuit with a graphical user interface (GUI) and simulate the large-signal, small-signal and noise behaviour of the circuit.

Circuit Simulator - Animated electronic circuit simulator using ideal components to visualize voltage and current.

KiCad - A Cross Platform and Open Source Electronics Design Automation Suite

VeroRoute - Cross-platform software for producing Veroboard (stripboard), Perfboard, and single-sided PCB...