If you've ever gotten a call from a private caller on your Grand Central number and you want to call them back, now you can. This does not work with Google Voice. Log on to Grand Central and find a message you've received from a private caller. If you know the name of the caller, input it. This will help a lot. Mark the message as new. Now call your number and access the voicemail. Press 2 to return the call. It will return the call, but won't reveal the number. Now you can leave a message of your own.