Software for making plots of fictional waveforms (not simulation/measurements)

[TheUnnamedNewbie]

For reports, it is not uncommon that one might want to add plots of fictional waveforms to show the intended operation of a circuit or such (take for example the output of a integrator or a bridge rectifier). These are often idealized circuits and so just taking measurements or even simulations doesn't work. Do you guys have any suggestions for making plots like this? I can of course use a ideal simulation, but that is not always easy. I can also come up with the mathematical descriptions of the waveform and plug them into matlab (which is what I tend to do now).

Do you guys know of any tools that make this even easier? Something that will allow me to just drag around waveforms or such, that I can perhaps export to something like inkscape to plug into my vector graphic schematics, etc...