Rat tail cactus (Disocactus flagelliformis). Has a bad name with its long drooping stems... but surprised me this spring with a nice display. Always a good conversation plant here even when it has no blooms.
When planting succulents in containers use commercial cactus soil, which usually contains finely milled peat and sand. To this, he adds a product called Turfis, used by bonsai experts to aerate the soil, but says fine gravel works equally well. Mix the cactus soil and gravel in equal proportions and, voilà, the ideal planting medium.