Treemap of Life
Simple HTML-based treemap
Displaying Catalogue of Life 2008 classification. Each taxon is drawn proportional to log10(n + 1), where n is the number of terminal taxa (i.e., species or below) in that taxon (the number of terminals is shown in each cell).
Link to Life
Link to functional Treemap (this is just the first node, there plenty more beyond this one).