On Ask Different there are many questions regarding the
PATH environment variable and how to set it for applications launched by a shell, by spotlight or via the finder (typical questions: How to set PATH for Finder-launched applications or How to change PATH environment variable...).
Answers range from
sh startup scripts to
/etc/launchd.conf. Here I am after the answer for a unified setting of
PATH for all apps under Mac OS X Mountain Lion 10.8.2.