If you've been keeping tabs on Filippo Battaglia's Nanodesktop programming library on the PSP, we've got some good news coming in. pegasus2000 is releasing a proof-of-concept system that's expect to release with Nanodesktop 0.4, dubbed the Nanodesktop FLite Voice Synthetizer. Here's a short description for the application, according to pegasus2000:

ndFLite uses VFPU to increase the speed of voice synthesis. It uses also Envelope Interface, a new API integrated in Nanodesktop 0.4 that ensures sound reproduction without glitches and MP3 reproduction with low use of CPU (Media Engine based).