7 World Trade Center 

This building was the first office building in New York to earn LEED certification when it was completed in 2006. Begun in 2002 after the original was destroyed in the September 11, 2001 attacks, the 52 story glass tower houses 42 stories of offices and an electrical substation that powers most of Lower Manhattan. The building earned gold status for sustainable core and shell development, with massive windows providing a pleasing aesthetic and low energy natural lighting. The building also features a number of works of art by artists such as Jeff Koons.

Nationals Park 

The first stadium in the US to earn a LEED certification, the stadium is a far sight better than the Washington team that plays in it. Opening in 2008 in a Southeast Washington neighborhood formerly considered one of the more dangerous in the city, the $611 million ballbark was completed in just two years. It features low flow plumbing and sustainable energy use.

Crowfoot Public Library 

The new Crowfoot Public Library in Calgary, Alberta holds the unique distinction of being the only building in Canada with LEED certification. As LEED certification is granted by the US Green Building Council, it generally means that only American buildings receive the award. However, the library was granted special permission for its efforts, including maximized natural lighting, several different water saving measures and EnergyStar roofing.

Grand Rapids Art Museum 

The Grand Rapids Art Museum in Michigan was the first museum in the world to earn LEED certification. Finished in 2007, the museum was named one of the top new buildings of the year by Newsweek. Its roof is designed to both reflect heat and collect water which is used for things like dishwashing and its reflecting pool. Its walls are made of locally sourced concrete, which goes with the locally sourced food in the cafe.

Center for Nanoscale Materials 

The Center for Nanoscale Materials is located at the Argonne National Laboratory in Illinois. Maximizing light and energy use earned it a bronze LEED certification. The center is one of two nanotech centers that are LEED certified, along with the Center for Nanophase Materials Science at Oak Ridge National Laboratory, so perhaps there is a strange connection between green design and nanotechnology that has yet to be fully explored.

William Jefferson Clinton Presidential Center and Park 

Bill Clinton's Presidential Library lies in Little Rock, Arkansas, where he first made his name as governor. In 2007 it became the first non-new build federal building to be awarded a Platinum LEED certification. The center has a green roof that reduces energy costs while saving water and giving plants a habitat. It is also partially powered by solar panels and uses green cleaning products.

Kansas City Science and Technology Center 

The KCSTC is owned and operated by the US EPA. It is one of the agency's showpieces for their “greening the EPA” initiative, which will see the EPA itself implement some of the advice they've been giving regarding building in sustainable ways. It achieved a Gold LEED certification for such features as low water flow plumbing, maximized natural day lighting, and sustainable wood sourcing.

Brooklyn Children's Museum 

The new Brooklyn Children's Museum recently became New York's first LEED certified museum. It looks a little like a giant banana or wedge of cheese, and the wacky architecture continues within. It was designed to conserve a maximum of energy, with solar panels providing much of its power. Also, it is built almost exclusively out of sustainable or recyclable materials like cork and bamboo.

Children's Discovery Museum 

The Children's Discovery Museum in Normal, Illinois earned its LEED certification in 2005. It was awarded a silver certification for using sustainable power sources and building materials, as well as eco friendly paints and cleaning products.

Burchfield Penney Art Center 

The Burchfield Penney Art Center is probably Western New York's premiere art museum. Newly opened at Buffalo State College, the museum's building achieved a gold LEED certification for reduced water use and improved efficiency in water and energy use, green construction materials, and innovation in green design.