I sing all the time, mostly in the car where I can pick and play my own choice of music.
Today I sang all afternoon while painting the bedroom wall. I played the Bee Gees Love Songs, and Chris de Burgh's Live in Dortmund - great stuff!
I also sang as a career for about 6 years, as a childrens' entertainer, and even recorded an album. Still have it on cassette, and it still freaks me out to listen to it!