LaTeX Drawing Circuits for LaTeX - Tool Recommendations

[Dragonfall]

I need to draw some circuits and importing them into latex. Any recommendations for a good tool?

 

[gsal]

I have not had to use them, but I have been curious before and found a couple:

http://sourceforge.net/projects/tinycad/
http://en.wikipedia.org/wiki/Quite_Universal_Circuit_Simulator

http://www.circuit-diagram.org/

Then, you can also draw the circuits directly from within latex with circuitikz

 

[Dragonfall]

Thanks.