Sometimes, when I download apps that haven't been signed, I get a warning that "X.app can’t be opened because it is from an unidentified developer". I don't want to change my Gatekeeper settings, so I made this workflow.

This workflow removes the extended attribute com.apple.quarantine from the specified application or preference pane.

keyword: rem   Just type in "rem" and then type in the name of the app you'd like to remove the warning from. The workflow searches for all .app and .prefPane files in your default search scope.