Every December, the nation’s most famous Norway spruce, New York City’s Rockefeller Center Christmas tree, is brought to life in a big-deal public lighting ceremony.

Festooned with 30,000 energy-efficient LED lights and a glittering 550-pound Swarovski crystal star, the Rockefeller Center Christmas tree is an impressive and iconic — and since 2007, green — sight to behold. But despite recent eco-friendly adjustments, this much-adored Christmas tree is traditional in appearance.

Below are five nontraditional public Christmas trees from aroung the world that are awe-inspiring — but not for the same reasons as the tree at Rockefeller Center.

Christmas tree at Enoshimo Aquarium in Kamakura, Japan

Although the Christmas tree itself at this aquarium outside of Tokyo isn’t too outlandish in appearance, it’s how the lights covering the tree are powered that’s rather unusual: eel power. For the past five years, the aquarium has rigged an electric eel’s tank with aluminum panels that capture the 800 watts of electricity generated each time the eel moves. This energy is stored and used to light the tree and, as a result, wows visitors and inspires headlines like “It’s beginning to 'eel' a lot like Christmas.”

This year, the eel-powered Christmas tree is joined by a people-powered animatronic Santa Claus that sings and dances when aquarium visitors stomp on a pad.

Lobster trap tree in Rockland, Maine

Like the eel-powered Christmas tree in Japan, there’s something fishy going on with the Christmas tree in Rockland, Maine: it’s composed of lobster traps. Although Rockland isn’t the only New England community with a lobster trap tree — Beals Island in Maine and Gloucester, Massachusetts, also have them — this one is perhaps the most famous given that Rockland refers to itself as the “Lobster Capital of the World.”

Rockland’s Christmas tree is a 30-foot tower composed of 152 stacked lobster traps. The structure is trimmed with pine garland and lobster buoys and built by volunteers. In 2010 the Rockland tree will receive an additional dose of fame as one of subjects of a Discovery Channel documentary about extreme Christmas trees.

Shopping cart Christmas tree in Emeryville, California

Not surprisingly, the Bay Area is filled with Christmas trees that can be classified as unconventional. But installation artist Anthony Schmitt’s Shopping Cart Christmas Tree in Emeryville is easily the strangest and most symbolic of them all, a festive comment on the relentless consumerism that drives the season. The tree is a 33-foot tall stack of recycled shopping carts, 84 in all, decorated with lights and ornaments. Although this is the first year that Emeryville has hosted a Christmas tree made from shopping carts, Schmitt has erected a similar structure in Santa Monica for the past 15 years. The location of Schmitt’s Emeryville tree? A bustling shopping center, naturally.

Pac Man Christmas tree in Madrid, Spain

Delighting the public and stirring the hearts of videogame geeks worldwide, a fully animated Pac Man Christmas Tree appeared at Nuevos Ministerios in Madrid in 2007. It’s unclear if this joyous, arcade-themed LED holiday display has been installed in subsequent years or if was just a one-off installation. Also no word if the Pac Man Christmas tree designers plan on tackling Tetris or Galaga in the near future.

Tumbleweed Christmas tree in Chandler, Arizona

While many parts of the world are blessed with having perfectly suitable traditional Christmas trees within convenient chopping distance, this isn’t quite the case in the desert town of Chandler, Ariz., a suburb of Phoenix.

Instead of importing a fir from afar, the creative and resourceful residents of Chandler have been erecting a Tumbleweed Christmas tree since 1957. Located in A.J. Chandler Park, the 2010 Tumbleweed Christmas tree consists of more than 1,000 tumbleweeds collected by city workers especially for the tree. The tumbleweeds are placed in a 30-foot wire frame and covered with white paint, lights, flame retardant and enough glitter to keep Rip Taylor happy — 65 pounds of it.

Matt Hickman ( @mattyhick ) writes about design, architecture and the intersection between the natural world and the built environment.

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