Add another instance of a call but no message. I force all of my unknown calls on my cell phone to my Google Voice number. Any voicemail left there will be transcribed into a text message which is sent to my cell phone. I can then easily see what the call was about and if I need to call the person back. Seems to have cut down on the number of spam messages ("You have been approved for a pay day loan!") that used to be recorded on my AT&T VM.