Bookmarks for mp3 idea

I listen to a lot of audio books and podcasts and have a habit of
listening to a few of them concurrently.

Bookmarks that I can set in individual mp3 files would help me
greatly, likewise, it would be wonderful if when I pause or stop a
file, a bookmark of the abandoned spot that is generated automatically
would be ever so useful.  In fact, a list of the last n of each type
would be even better! :)

cheers,

Gabriela