Thought to have been long extinct for 100 million years, and known only from fossil records, the Wollemi pine (Wollemia nobilis) became a botanical revelation in 1994, when a few dozen specimens were discovered in a deep ravine in the Blue Mountains, 100 miles west of Sydney, Australia. The director of the Sydney Royal Botanical Gardens was quoted as saying this discovery was "the equivalent of finding a small dinosaur still alive on Earth." The tree is from the Araucaria family, and so is a relative of the Norfolk Island pine, monkey puzzle tree; bunya-bunya, cook pine, etc.
The location of the 100 or so Wollemi pines was initially kept secret, to protect the small grove of trees. Before announcing the discovery, the Sydney Royal Botanical Garden propagated cuttings and distributed them worldwide to botanical gardens and nurseries before announcing the discovery.
There are only two outdoor specimens of Wollemi pine that I know of in San Francisco, and they're both in the Botanical Garden, in the Ancient Plant Garden. Both were received in 2004, so they're about 10 years old. The adjacent photo is one of them.
This is probably not a good street tree for planting in sidewalk cuts, but I think it’s a great choice for side yards or open spaces. Hello, Recreation and Park Department? Hello, Presidio Trust? The trees are very easy to order commercially (I was surprised recently to discover that some friends had a Wollemi pine in a pot in their living room). If you want to participate in the effort to get more of this interesting species planted in San Francisco, you can order one here: http://www.wollemipine.com/index.php