"Auno's Damage Dumper" is a small PHP program that uses the GTK PHP bindings to produce a sortable table of damage dealt in AO. It reads the damage from a log file produced by AO. The program also displays a SK-meter that tells you how much SK you have gained since you last reset the dumper, and also your hourly SK rate.
The older versions suffered from various problems, including not recording some damage (mainly perk specials and damage shields) plus the difficulty of setting it up, but the current version automatically creates a window with the required settings. A remaining problem is the ugliness that is caused by the old GTK-1.2 widgets. The next version of PHP-GTK is supposed to be based on GTK-2, but I have no idea when it would be available.
You can get the full version (including PHP and GTK files) from http://auno.org/aunodd/damagedumper.zip, or if you only want to upgrade your current version, get only the damagedumper.phpgtk file and replace your existing one with the new version.
If you are running the damagedumper for the first time (or for the first time for another character), you must have AO closed when you start it the first time. After starting you should hit the 'Select Char' button and find your character preference folder, for example C:\Games\AO\Prefs\MyAccount\Char192839, and hit OK. Also, just to get the damagedumper fire up you will most likely have to edit the supplied shortcut and fix the damagedumper path to point to the directory where you unzipped it.