Analog Circuit Design - Symbolic Modeling and Analysis Methods
http://www.analog-insydes.de/
Design, simulate and learn about electronic circuits
http://ourworld.compuserve.com/homepages/Cherrywood/cshop1.htm
Analog & Mixed Signal Simulation Software
http://www.intusoft.com/demos.htm
with Schematic Capture
http://www.anasoft.co.uk/
general purpose nonlinear circuit, system, and electromagnetic FDTD simulation and design program
http://www.aplac.hut.fi/aplac/general.html
Analogue Circuit Analysis Software
http://www.te.rl.ac.uk/europractice/univs/avanti.html
from Electronics Workbench
http://www.electronicsworkbench.com/
The Intelligent Symbolic Design System for Analog Circuits
http://www.itwm.uni-kl.de/as/products/ai