last.fm is a great service. If you haven't heard of it before, it's basically personalized streaming internet radio, with a recommendation, and song/artist/album tagging. One of the nice things about it is that you can stream tagged music. For example, streaming lastfm://globaltags/futurepop would give you a stream made up of all things tagged 'futurepop' by last.fm's users. Subscribers get a further feature -- they can stream their own tags. This is all very nice, but tagging is generally done from within the last.fm player, or from their web interface. What I wanted to do is to script the tagging so that I could tag artists programmatically...