gnome-session-propertiesgnome-session-properties can be used to configure startup applications.
Also, if you want an application to run at system boot, you can add a rule like the following to your crontab (edit crontab with "crontab -e"crontab -e).
@reboot /run/this/program/at/boot >/dev/null 2>&1:
@reboot /run/this/program/at/boot >/dev/null 2>&1