From Centigram Communications:
TruVoice is an advanced text-to-speech converter you can use to give speech capabilities to animated characters developed with the Microsoft Agent ActiveX control. TruVoice can convert any text into highly intelligible, natural-sounding speech for any sound-enabled platform. The program also provides developers with an application programming interface to simplify the integration effort. Adding speech to any application is as easy as printing or producing a "beep" sound. Simply input a text string, and the computer's sound system will say it.