A droplet to identify potential duplicate files - Drop a file on it and it will use your Spotlight index to see if you have a potential duplicate somewhere.

Based on this hint: http://www.macosxhints.com/article.php?story=20061003163429425 at macosxhints.com, which contains the history & source of the underlying script. Thanks again to the bash gurus there who vastly improved my original script.