Speech Queue for Mac

From Rainbow Flight:

This program is an Apple Scriptable utility and text service to speak text with customizable voices using Apple's Text-To-Speak.
Features:

• Speaks the text message in the assigned voice.
• Speaks messages in the order recieved.
• The user can pause, un-pause, or stop speaking the messages.
• Text Service for Speech Queue to allow text from other Cocoa applications to be spoken.
• Applescript support allows scripts to speak text without worrying about having the script pause until it is done speaking.
• User defined voices can set custom voice name, rate, pitch, modulation, and volume.