Need something substantial, maybe for a small tree on a terrace or something near an entryway? These planters have a lot going for them...
These are 'Madison' resin planters, and they have a very pleasant soft, sanded look. They are double-walled and can handle the weight of the soil, water and whatever plant would go into them. Their extremely light weight also keeps them manageable (especially compared to other materials at this weight and thickness) once they are full. And they are very durable.
The photo above was from the New York Botanical Garden's shop, and they are available through their online shop.
Simply Planters is another online resource that has more and better photos as well as complete dimensions:
matt at apartment therapy dot com