I was going to add a bit of information to my post on a previous day using schematics and some instructions. What programs are being employed for this purpose?

I mostly want to see what others are using and that I can easily use to give descriptive schematics.

In a perfect world, and I know this is a case of me wishing, it would be:


Free.
Extremely easy to draw schematics
in.
Allows simple production of
waveforms for the inputs/outputs.


Try KiCAD. Now it even does SPICE simulations, ngspice specifically, and it handles pretty much everything else. Other than that, if you wish, KiCAD has also the tools to design printed circuit boards, and even has a 3D viewer and exporter for the boards!
KiCAD runs on Windows, Linux and Apple OS X.
There is also a project called ESIM that bundles KiCAD with a SPICE simulator and differential equation solver.
