They are called Magnaturals, and made by Pet Tech. New England Hepetoculture sells them, and they have pics there. The ledges and planters are made to support gekos, but the magnets are VERY strong, and this snake only weighs 200-something grams. (33 inches long, and slender, but not skinny.)

I really like the way they look. (Just have to be careful to keep the magnets away from sensitive electronics.)