software synthesizers for linux speech

[Kyle]

eSpeak is part of the Ubuntu distribution, and if you boot into the 
speaking desktop, eSpeak will run automatically. If eSpeak isn't to your 
liking, you can install libttspico, which should speak with the latest 
speech-dispatcher. This is the SVox Pico speech synthesizer that is 
installed on Android devices. Both options are free as in speech and as 
in beer, and both are responsive and easy to understand.
~Kyle