Billy Bryans turned me on to this and now I just can't turn it off. It's called PJ Radio – an Internet-based radio station programmed by, presumably, a guy named PJ out of Toronto. PJ Radio is streamed through Apple's iTunes, the first time I've come across such a feed that wasn't part of the pre-programmed package from Apple.
The sound quality is terrific and PJ's musical moods so far this afternoon are right in step with mine.