Development System for Auditory Modelling: Software that models the auditory system.
IPACLICK: A freely accessible phonetic type-and-clickwriter for IPA symbols in Unicode. Also includes "superlinguistic" names of consonants shown in phonetic script.
JavaSpeechLab: Speech analysis software written in Java 1.1.
JSyn - Java Audio Synthesis: Java API for real-time audio synthesis and computer music.
Optimality Theory Software: OTSoft is meant to facilitate analysis in Optimality Theory (Prince and Smolensky 1993) by using algorithms to do work that would have to be done (tediously, and perhaps unreliably) by hand. [by Bruce Hayes, UCLA]
Praat - A system for doing phonetics by computer: Free software for acoustic analysis. (by Paul Boersma, University of Amsterdam)
Speech Filing System Home Page: Acoustic analysis software for Windows and Unix.
Speech Synthesis and Analysis Software: Listing of software for speech synthesis and analysis.