Senecio rowleyanus - String of Pearls
String of Pearls is a trailing succulent with stems that grow up to 2 - 3 feet long with pea-shaped leaves that retain water. It is native to very dry, arid climates in Namibia and won't need a lot of water to thrive. The round shape of the leaves minimizes the surface area exposed to dry desert air and therefore reduces evaporation.
This plant is both fascinating and puts on quite the cascading display among your hanging pots.