This script monitors your music folder and keeps track of what songs are played by anything other than your main iTunes application. It then updates iTunes with the correct playcount and last played date. This allows you to keep iTunes playcounts and last played dates accurate, regardless of what application or device you use to listen to your music. Basically any playback method which accesses your music folder is supported, including iTunes music sharing and the use of networked audio players such as the Soundbridge or Squeezebox. ReadMe is a must-read.
Not sure how well this works in Tiger and onward.
OBLIGATORY WARNING! Because this script has been designated as a "Retro Script" there is no guarantee that it will function as described and may even corrupt or destroy data.