Similar to what we experienced with Musicovery , where you search web radio according to your mood, Moody  allows you to tag the tunes you already have by the way they make you feel.
Tags are color coded and their names are customized any way you want them to be. Have tons of Al Green? He might be a little more towards the red end of the color spectrum, under the "Gettin' in the Mood" tag if you know what I mean. Whereas, Daft Punk might be a yellow "Lets Dance!" tag. It's all up to you! You can even label your tunes as you listen, so you don't have to sit for hours tagging photos when you should be doing other, more productive things — like reading geeksugar, of course! Moody is free and available for iTunes on OSX and Windows.