SimpleSong is an application which allows you to easily write songs for your Macintosh to sing. Songs written with SimpleSong can also be sung using any text-to-speech compatible application, such as SimpleText. This means that almost any Mac user can listen to the songs you've written.
Some possible uses:
Send some singing e-mail!
Add a synthetic "vocal" track to your electronic or accoustic music.
Liven up a meeting or gathering with some unexpected vocal "talent".
Freeware by Useful Software