Howto access an activity sub-directory?

[Kent Loobey]

I am trying to get at a resource in my activities "fonts" sub-directory.  My 
activity finds it just fine when running under Sugar but can't find it with 
the same code when running in a shell.

        self.fontPath = os.path.join( 'fonts', 'DesiredResouce.ttf' )
        self.desiredFont = pygame.font.Font( self.fontPath, 96 )

Any suggestions?