gtk+ 2.0 Change Theme is a tiny GUI application that aims to make GTK+ theme preview and selection as slick as possible. GTK+ themes installed on the system are presented for selection and previewed on the fly. It supplies a large variety of widgets for a comprehensive demonstration.
GARP (Gnome ARP) is an ARP monitoring program written on Gnome with the GTK toolkit and Ruby. It takes ARP tables and some system variables via SNMP and ARP protocols and determines whether any machines have changed their IP address. It is useful for detecting new machines on the network and detecting which machine have changed addresses. It is intended especially for network admins.