According to Magnum-Opus, prolific composers Dr.Sonique and Jon Drummond wrote an enormous number of very brief diatonic "melody modules" back in the 1970s. They've recently discovered that people have been performing these compositions (without proper permission or attribution) when making telephone calls. They provide a mechanism whereby you can determine whether a given telephone number corresponds to one of their copyrighted melodies; if it does, they provide you with the option of either licensing the melody (a variety of licensing options, at various prices), or disposing of your telecommunications device.
And because I know from long experience that people don't recognize my deadpan statements on Web pages as humor, I feel obliged to note that yes, I'm aware that the site is a joke. And a good one.
It's an Australian page; unfortunately slow to load from the US. Parts of it appear to require the Flash plugin.