LazyWeb Request: Choon Button

A request to the all-powerful LazyWeb:
I want a button, either on a web page or floating around on my desktop. When I click it, it should discover what I’m currently listening to via the Audioscrobbler web services, then automatically add it to a playlist which I can later download, bookmark, etc.
Is there such a beast already?
Include an option to associate a tag, and I think this would be a much better way to organize a music collection that the current last.FM model. I’m pretty daunted by the prospect of going through manually tagging tracks as to do it properly I’d have to listen to everything in my collection. A knee-jerk quick categorisation whilst the player is in random would hit the sweet spot for me.