Disable Specular On All Scene Lights
This is an extremely simple and small script that disables Specular on ALL of your scene lights. It will ignore any incompatible lights such as Skylights.
This is useful particularly for Mental Ray renders. I personally never use Specular in any of my MR projects, since it often creates unwanted speckles and other issues.
Check the listener window for any errors once run.
To use simply run the script.
If you want to enable Specular on ALL your lights again you can simply open the script and change "off" to "on" and run it again.