Jyngle sends real-time mobile messages to groups
Social voice mail and SMS messaging.
It's a social network--set up groups online and make them public or private. From a phone, dial in, submit a PIN, record a message. The voice or text message is then sent to the mobile phones of the predetermined members of that group.
Brevient says the ideal application is event reminders or meeting changes. At first glance it seems a bit complicated, but probably useful for messages that need to be heard ASAP.