Intelli-Site provides Text to Speech. Some users need it some don't. It can be enable/disabled on a user by user basis and the voice used can be selected.
Procedure
The Text to Speech properties for a user can be found on the "Text To Speech" tab of a user's properties.
Setting the Text to Speech options:
In Design Mode:
Expand "System Control" -> "Users".
Right-click on the user node and select "Properties...". The properties for that user will appear.
Click on the "Text To Speech" tab. Here you can enable and disable Text to Speech by clicking on the check box. You can specifiy the desired voice, and modify the Volume, Rate, and Pitch of the voice.