When your five-year-old nephew sings "Happy Birthday" to you on your voicemail, you want to keep that message to play back to his friends when he's in college. If you've got an iPhone, there are a few ...

Lifehacker has two methods to do so, one using a jailbroken iPhone to save the actual audio file and a non-jailbroken method that uses the headphone jack and your computer's line-in to save the sound.