I'm into alot of organic matter and conserving materials so often times I end up making them out of old containers and butter dishes, they work for fast growers and self seeding plants. Theres one for my Mimosa right now that was made out of an old plastic rat tunnel, it helps recycle and by taking the old tunnels out I can give my lovely pets some new toys with the thought of future seasons in mind.
As long as you have some primed paint they don't even look like recycled pots, many of them remind me of the $12.95 nature pots in home centers and garden stores. If your really crafty I've discovered creating beaded loops and belts can make a butterdish into one amazing hanging planter! That also helps in showing the plant a little extra attention and personalizing your garden. With all the abilities for the new yogurt dishes and plastic wine bottles that just came out, Reduse,Reuse and Recycle has never been easier