From Rob Richler:
Created in response to requests on the Konfabulator forums, iRateIt is very minimalist on purpose. iRateIt displays the current iTunes song rating and updates when new song starts. iRateIt will update if you pass your mouse over it, in case you skipped a song.
You can set the song rating by clicking your mouse on the stars and dragging to the appropriate number of stars. There's an option in iRateIt preferences to display the name of the currently playing song: display player controls, set the star, control and text color, and automatically skip to next song when you rate a song below a certain rating. This version is the first release on CNET Download.com.