EPulse is a signal generator, that can be used to produce simple sound effects or to act as a very universal function generator for electronics.
EPulse reads its configuration from an XML file, and writes the output in a .WAV audio file. Currently only mono signals are generated, but multichannel files will be supported in the future. It can generate signals with an unlimited level of modulation: each elementary waveform can be modulated in amplitude, frequency and phase, and the modulating waveforms can be modulated in turn.
A signal can be divided in sections. Each section has different modulation parameters, and it is possible to give a program that gives which sections to use, in what order and for how long. Loops can also be created.
EPulse is opensource, with a MIT license, which basically means that you can download the source code and do whatever you want with it, including using it in closed source product, as long as you include the copyright notice.
To download EPulse and for more information, check out the epulse web site and the epulse sourceforge project.