Spice+ is a general-purpose circuit simulation program based directly on Spice3f5. Its main purpose is to allow university students and other interested people to simulate their circuits without buying expensive simulation programs or being limited by free trial versions of such software. Since source code is available, students or researchers can use it as a basis for new models and algorithms.
Slam is a mature IC Layout editor with the ability to edit very large designs (such as stream files larger than 10GB). Novel features include threading for redraw, support for displaying on multiple X servers simultaneously, and a Tcl interface to the database for user extensibility. The system is a library based system with multi-user support. Programmable structures (P-Cells) are available in Tcl. The editor includes gds input and output.
ElectricFormula is a program that can help with electronic based projects or problems. It can calculate electric power, resistance, current, or voltage. If given two of these variables as input, it can determine the other two. For example, if you want to calculate the resistance, you will have to supply the value for the electric power and current or you can supply the value of the power and voltage.