Answer #3 (maybe indicating that the questions wasn't exactly precise ;-):

On Thu, 8 Feb 2007, Ioannis Vranos wrote:

> How can I make a given script or an executable to run during start up, 
> system-wide? I am using GNOME and I suppose I can place it on the "Startup 
> Programs" in "Sessions" for every user, but I suppose there is a more elegant 
> approach to this.

If "during start up" means "at the beginning of every GNOME session, 
before GNOME is actually launched", just add a bash script in
/etc/X11/xinit/xinitrc.d. From my notes:

# Call chain:
#  gdm
#   runs     /etc/X11/xdm/Xsession
#   sources  /etc/X11/xinit/xinitrc-common
#   sources  /etc/X11/xinit/xinitrc.d/*.sh
#
# Note: These are NOT sourced in failsafe sessions.

-- 
Stephan Wiesand
   DESY - DV -
   Platanenallee 6
   15738 Zeuthen, Germany