Tangram is the famous puzzle with 7 shapes that don't over lap that then create an complete shape of say a person or animal etc...
Lago have used the idea to create these shelves, of course you can buy and arrange them how you'd like but the photo show how well it can work to make a focal point in a contemporary or modern living space or office.
Functionally the shelves will not hold many books or items but the point is to create and graphical focal element vs its use.
If you want the history of Tangram then check out wiki http://en.wikipedia.org/wiki/Tangram
To view other formations and idea check out the Lago website.