iScrobble Premium has now made its way to the Mac App Store!
It gives you a convenient way to control iTunes even when iTunes is minimised and gives you the ability to quickly change track, play, pause and see what is playing.
It will submit scrobbles to last.fm using a lightweight app that doesn't get in the way of everything else you do.
It launches when iTunes opens automatically and closes when iTunes quits just to make sure that it is not wasting resources.
It will Save scrobbles for later if there is no network connection and will scrobble when it regains network (if you quit the app it will scrobble next time you run the app with a network connection!).