Last.fm (which tracks played music) could already recommend me some good music ten years ago... It could even tell why it recommended something ("because you li

Last.fm (which tracks played music) could already recommend me some good music ten years ago... It could even tell why it recommended something ("because you like X and Y"). They even had a fricken desktop app for Linux to play their personalized radio! Today, well the basic tracking funtionality still works...