Leaving a Voicemail Without Ringing the Phone
This is a rather offbeat article, but an interesting read nonetheless. Recently I discovered a way to leave a voicemail message on someone's phone without actually calling them and having their phone ring. I tested this on a Verizon to Verizon cell phone call, so if you are using a different carrier, please leave a comment and tell if it worked for you.
Essentially, this process involves calling your own voicemail, entering a destination number, and then recording a message. That person will then receive a notification that they have a new voicemail, but their phone will never have rung. This is convenient if you want to leave a message for someone when they are sleeping or in an area where answering the phone isn't possible. It's also a great way to confuse people if that's what you're aiming for.
How It Works
To execute this incredibly interesting trick, call your own voicemail by dialing *86 or whatever number you use. Enter your password. Then, listen to the prompts and enter the main menu. Usually, you will hear a voice saying "No new messages, to enter the main menu, press 1." The message may be different depending on your carrier. Again, I'm not sure if this works on a different carrier or not, but it does for Verizon.
Once you're in the main menu, press 2 to send a message (or whatever number the prompt tells you). Follow the prompts to record a message. When you're finished, press #. Then enter a destination number and press # again. There may be a few more options to go through, depending on your phone. When you're finished, hang up and the person will be notified that they have a new voicemail. However, their phone will never ring during the process. (Their phone may beep depending on whether or not they have a voicemail notification alert).
That's all there is to sending a voicemail to someone without ringing their phone.