Forgot to post about this a few days ago when I actually updated the script.
Now Where Was I? v2.0 is a simple applet that, when run while a track is playing or paused, will "remember" the current track and quit iTunes; when it is next run it will launch iTunes and play that track. If a track is set to "Remember playback position", it will pick up playing from where it left off.
This latest version is generally updated for newer versions of iTunes and the Mac OS. More info and download is here.