Talking Calendar

Talking Calendar integrates with your Android™/Google calendar and reads aloud your calendar event(s) at the specified time(s) using the Android™ Text-to-Speech (TTS) library.

It respects your volume settings (it will only talk if you are not on vibrate or silent), and provides privacy option to speak, for example, only when not on speakerphone, or only when on Bluetooth.

It requires no ongoing user intervention!

Now you don't need to fidget with your phone to see upcoming events, and neither do you need to put on your reading glasses. Great for hands-free convenience, and great while on the road!

One of the recommended apps on Androinica.com. Here is the link:
http://androinica.com/2010/05/16/android-apps-alert-22-read-the-times-and-slice-your-music-edition/