Festival Speech Synthesis
Festival 1.95 doesn't build on a Mac at all, 1.96 only builds if you do what's described on these two pages:
http://www-personal.umich.edu/~clunis/festival_macbook.html
Note that the festlang-talk page in the first link is dead. The actual post is the link below
http://lists.berlios.de/pipermail/festlang-talk/2008-January/000792.html