Elan Speech
Offers Elan Sayso natural sounding text-to-speech for Mac OS X. Available in 12 languages.
IBM ViaVoice (US English)
Continuous speech recognition for your Mac.
MacSpeech
Home of iListen, a Speech Dictation/Command software for Mac OS. Includes news releases, online store, and tech support.
Speech Technologies (Apple)
Apple?s Speech Recognition and Speech Synthesis Technologies now give speech-savvy applications the power to carry out your voice commands, and even speak back to you in plain English, and now, Spanish.
Speechissimo
Converts any written text into speech using Elan Sayso text-to-speech technology. Speechissimo can speak multiple common languages. For Mac OS X.