There is a building being built in Taipei for the Flora Expo in 2010. It is walls and roof is made out of 100% recycled plastic bricks called Polli-bricks.
These innovative bricks are made by Miniwiz S.E.D.
The bricks interlock to create a large structure that can withstand many extreme weather conditions. Also, the bricks can be filled with all sorts of materials.
The building is quite pretty.
One thing that I think is especially cool is that there is a water fountain on one side for cooling in the building. The whole design is ecofriendly, even the air ventilation.
Here's a picture of it:
Hope you like this