Can I change the locale for a single application? Is it possible to change the locale on a per-application basis in OS X 10.8? Background: I'd like to play "Larry Reloaded" in English, but my user locale is German. The game detects this, and switches to German voices and texts. I don't want to create a new user just for the game, nor do I want to switch the locale manually when starting the game, and back again after quitting.
You can add an AppleLanguages array to the plist of an application:

defaults write -app Calculator AppleLanguages -array de


See defaults read -g AppleLanguages for the language identifiers.

Language Switcher is a GUI for doing the same thing.