Orchids are especially common in the tropics but will grow just about anywhere and are extremely varied. Most orchid fruits produce a huge amount of seeds, sometimes in the millions. These seeds are generally only a few cells and require a special relationship with a mycorrhizal fungus to germinate (thanks again fungi!).
I also just learned today that vanilla is an orchid. Beautiful and delicious!
Stern, Kingsley R. (2006) Introductory Plant Biology, Edition Ten. New York, NY: McGraw Higher Education.