SayNow makes it easy for you to broadcast voice, photos, and text messages from your phone to all your fans.

You can also:

-Listen to messages from your fans
-Reply to your fans
-Call individual fans back (and keep your real number private)
-Save your favorite messages
-Forward messages to friends
-Block callers you don’t want to hear from again

http://appshopper.com/social-networking/saynow