If you use nagios with checkcommands, you can use this to define DEFAULT for nagios checkcommands.

# Define default values in generic service
define service{
        name                           generic-service
        use                 graphed-service
        active_checks_enabled          1
        passive_checks_enabled         1

        ...

        __CHECK_HTTP_ENHANCED_PORT 80
        __CHECK_HTTP_ENHANCED_SSL off
        __CHECK_HTTP_ENHANCED_AGENT "check_http_enhanced"
        __CHECK_HTTP_ENHANCED_URL "/"
        __CHECK_HTTP_ENHANCED_HOST $HOSTADDRESS$
        }

# Use default in checkcommand definition
define command{
        command_name   check_http_enhanced
        command_line   /etc/nagios/scripts/check_http_enhanced.pl \
                 -H $HOSTADDRESS$ \
                 -n $_SERVICE_CHECK_HTTP_ENHANCED_HOST$ \
                 -u $_SERVICE_CHECK_HTTP_ENHANCED_URL$ \
                 -p $_SERVICE_CHECK_HTTP_ENHANCED_PORT$ \
                 -s $_SERVICE_CHECK_HTTP_ENHANCED_SSL$ \
                 -A $_SERVICE_CHECK_HTTP_ENHANCED_AGENT$
        }  

# Override default in service
define service{
        __CHECK_HTTP_ENHANCED_URL "/devel/"
        __CHECK_HTTP_ENHANCED_HOST "www.somesite.com"
        use                            generic-service
        host_name                      server22
        service_description            description
        check_command                  check_http_enhanced
        }

Na rozdiel od KDE, ktoré má defaultne zabudovaný menič obrázkov na pozadí, v GNOME som na priateľkynom pc nič také nenašiel. Takže trocha googliť a skipt je hotový.

#!/bin/bash
# $Id: change_gnome_wallpaper,v 1.1 2008/05/29 10:23:52 cvsoernii Exp $
DIR=/net/192.168.1.100/raid/fotky/_vytlacit/
FILE=$(for i in `find $DIR -type f`; do echo "$RANDOM $i"; done |sort|head -n1|cut -f2 -d" ")
gconftool-2 -s /desktop/gnome/background/picture_filename $FILE -t string