www.tokyocheapo.com:
The stuff of nightmares (for some) the Maman Spider Sculpture by Louise Bourgeois is a famous landmark in the busy city. Standing at a terrifying 30ft tall and 33ft wide, it is not the place to arrange to meet an arachnophobe (unless you really don’t like them). If you stand below the creature you can look up to see a cluster of 26 marble eggs held within an abdomen and thorax made of ribbed bronze. The Roppongi sculpture is one of 6 bronze castings which followed the original 1999 steel creation which was displayed in the Tate Modern, London.
As terrifying as it may seem to some, the statue reflects feelings of nurture, protection, weaving and spinning and is an ode to the artist’s mother who was a weaver by trade and died when Bourgeois was 21. The five matching statues can be found in Qatar the USA, South Korea, Spain and Canada.

www.wikipedia.org:
Not to be confused with Louise Bourgeois' similar sculptures: Spider or Crouching Spider
Maman (1999) is a bronze, stainless steel, and marble sculpture by the artist Louise Bourgeois. The sculpture, which depicts a spider, is among the world's largest, measuring over 30 ft high and over 33 ft wide (927 x 891 x 1024 cm). It includes a sac containing 32 marble eggs and its abdomen and thorax are made of ribbed bronze.
The title is the familiar French word for Mother (akin to Mummy). The sculpture was created in 1999 by Bourgeois as a part of her inaugural commission of The Unilever Series (2000), in the Turbine Hall at London's Tate Modern. This original was created in steel, with an edition of six subsequent castings in bronze.
The sculpture picks up the theme of the arachnid that Bourgeois had first contemplated in a small ink and charcoal drawing in 1947, continuing with her 1996 sculpture Spider. It alludes to the strength of Bourgeois' mother, with metaphors of spinning, weaving, nurture and protection. Her mother Josephine was a woman who repaired tapestries in her father's textile restoration workshop in Paris. When Bourgeois was twenty-one, she lost her mother to an unknown illness. A few days after her mother's passing, in front of her father (who did not seem to take his daughter's despair seriously), Louise threw herself into the Bièvre River; he swam to her rescue.
The Spider is an ode to my mother. She was my best friend. Like a spider, my mother was a weaver. My family was in the business of tapestry restoration, and my mother was in charge of the workshop. Like spiders, my mother was very clever. Spiders are friendly presences that eat mosquitoes. We know that mosquitoes spread diseases and are therefore unwanted. So, spiders are helpful and protective, just like my mother.
Louise Bourgeois
Some of these editions in permanent collections often tour on exhibit:
Tate Modern, UK – The permanent acquisition of this sculpture in 2008 is considered one of the Tate Modern's historical moments. Maman was first exhibited in the turbine hall and later displayed outside the gallery in 2000. It was received with mixed reactions of amazement and amusement. The sculpture owned by the Tate Modern is the only one made from stainless steel.
National Gallery of Canada, Canada – The National Gallery of Canada acquired the sculpture in 2005 for 3.2 million dollars. At that time, the price was deemed excessive by some critics, as it took around a third of the annual budget of the gallery.
Guggenheim Museum Bilbao, Spain.
Mori Art Museum, Tokyo, Japan[8] – On display at the base of Mori Tower, outside the museum.
Leeum, Samsung Museum of Art, South Korea.
Crystal Bridges Museum of American Art, Bentonville, Arkansas, USA.
Qatar National Convention Center, Doha, Qatar.