Festival is a speech synthesiser created at University of Edinbourgh.
Requires Linux.

Installation instructions.
1) emerge Festival
2) replace tts.scm with this one tts.txt (rename to .scm)

SpeechPlanner (speechrenderer): http://cadia.ru.is/wiki/public:speech_renderer
Speaker: http://cadia.ru.is/wiki/public:speech_player