A long time back I found all the AT&T voice pieces in a set of .wav files. I made an answering machine message that said, "I'm sorry... the number you have dialed xxx-xxxx is no longer in service. You can reach your party at their new number, 911." Something to that affect. I don't think many people even got to my phone number before they hung up. I changed it shortly thereafter.
On a recent Spurs trip, we were asking one of our sponsors who works at Jack in the Box for some funny stories or experiences with the company. The funniest story he had was when an operations manager was late for a meeting and called his boss to tell him he was running late. As he was leaving the voice mail message, he witnessed an accident and went on to provide “play by play” of the incident.

Thanks for calling Dial-A-Shrink. I can’t come to the phone right now, so after the tone, please leave your name and number, then talk briefly about your childhood and tell me what comes to mind when you hear the following words: orange… mother… unicorn… penis. I’ll get back to you with my diagnosis as soon as possible.
Once you have your message, you need to actually record it. The exact process varies depending on whether you’re using a cell phone or office phone, but here’s the basic process: Press the voicemail button, or press and hold 1 on most cell phones. Enter your password. Record your message. Listen to the message you just recorded. Follow the prompts to save your message. Following Up on Voicemail Messages