Recently, on two separate trips, I spied some really spiffy concrete planters. The first trip was at the New York Botanical Garden, where they were used by the rock garden area (at left).

I thought they looked fantastic and the selection of plants - mainly succulents and small conifers- coordinated well. It wasn't until I took a trip to Quackin' Grass Nursery that I understood how these were possibly made... - Matt N.