I have my car mp3 player 90% complete and almost matches all of my requests

I want to be able to press a button and the currently played song could be:

either:
copied to another folder or into a seperate playlist.
Or somehow tagged with text or something.

Why:
In my car I stream hours of music and out of the 600 random songs, some of them I like. I would like to easily press a button to identify that song as a 'keeper' that way when I clean up and delete my streamed music offline I can save/move my bookmarked files. It would be great if I could copy them to another folder or a playlist while playing. That way the process is automated.

Is there a plugin for this? how do bookmarks works? can I assigned bookmarked mp3 to a seperate playlist (called favorites) that way I can just load the favorites list whenever and it will have all of my bookmarked songs