I love to sing. I had actually forgotten how much I love to sing until my son was born-now I sing daily. I sing in the car with the radio, while cooking, while dancing and make up songs with my son. He loves to sing too, and a recent favorite of his is now "Walking on the Moon" by the Police. I wouldn't say I have the worst voice, but I'm no Alecia Keys and some days he's had enough and it's "stop singing Mommy!" There are some days though that I don't sing as much for whatever reason, and I have noticed there is a marked difference in my mood.
The vibrations that travel through the body through singing can release blocked energy and relieve tension, especially in the chest area, where tonal vibrations are most intense. This is due in part to the vibrations themselves which can travel through muscle, bone, tissue and organs and act as a massage of sorts and also through the deep diaphragmatic breathing that is activated through singing.
Even if you think you don't have perfect pitch or an ear for music, try singing. And if you really don't want to sing, listen. There are just as many healthful benefits to listening to your favorite music. And who knows, maybe you'll even want to get up and dance!