a novel treemap data visualization approach that uses Voronoi tesselations (a polygon-based subdivision algorithm) instead of rectangular shapes. it attempts to avoid the problems with the aspect ratio of the rectangles as well as with identifying the visualized hierarchical structure. this approach allows for creating treemap visualizations within areas of arbitrary shape, such as triangles & circles (& in addition is also quite aesthetic).
see also smartmoney map & google newsmap & color project. [uni-konstanz.de (pdf)]