A tall pole with Pothos (Epipremnum aureum) trained up it. Pothos, or Devils Ivy, is a fast growing vine that is suitable for all conditions.
Use in tall enclosures, such as Water Dragons, Chameleons or Iguanas, to provide sturdy, live planted furniture to climb on. This plant will spread rapidly around the enclosure. They are easy to propogate using cuttings too, so you can easily add it to other tanks.
Warning: Pothos can be toxic to some animals. Whilst small amounts may not cause any illness, please bear this in mind if you find your animal eating large amounts of the plant.