In the gardening world, it is very trendy to make hypertufa garden troughs for planting succulents and miniature plants. Hypertufa is simply a man-made imitation of light weight tufa rock which can be molded into planters. Troughs are pretty easy to construct and a whole lot cheaper than purchasing a pre-made one. A sizeable trough around 15" long can set you back at least $50.
I'm obsessed with hypertufa!! :-)