Pandora - discover music
this one's a nice music service.. similar to any other radio station.. but works differently..
give it a song/artist to start off frm n it plays other songs similar in musical qualities to that song/similar to the typical style of that artist..
go to http://www.pandora.com n discover it urself..

this reminds me of moodlogic.. moodlogic does a similar thing, but it sorts music based on ur mood n plays songs based on ur current mood.. only difference here being other ppl have already sorted out n grouped songs based on their type, so u don't have to categorize songs as in moodlogic..

the homepage says it belongs to a bigger project called Music Genome Project. sounds impressive.. even the songs it plays seem to hold its claim.. they're very similar to the intitial song.. if u can start wit a song typical to some mood, u can use it just like moodlogic..

one thing I dont like is that it's a radio.. :( i.e. I can't go back n play a song that's already played :( apart frm that, this service is really good..

I had an idea for an application which'd automatically analyze a song n categorize it under various labels.. then there needn't be any human intervention while rating music.. but it'd be a very complex application.. involving all sorts of intelligence.. DSP to start wit.. that'd b more like teachin computer to listen n analyze (enjoy?!) music.. that's the major reason why I've deferred startin on it.. other reason is the time factor.. but wud like to start it off some day..

n btw, I guess it's been written using Open Laszlo, but dunno for sure.. just guessin.. coz even I'm plannin to use Open Laszlo for my personal site n for a site being designed for my school..