A set of free User Defined Functions for Microsoft Excel® to create Sparklines :
the simple, intense, word-sized graphics invented by Edward Tufte & implemented by Fabrice Rimlinger.
It is now possible to create arrays of PieCharts, of variable sizes and colors, through the Heatmap() function. In addition to the disc position in the array, 3 variables are displayed :
Color scale
Size variation
Size of the slice
Obviously I do not recommend using it for large arrays, but I believe that it works pretty well up to 5 x 5 arrays and 4 colors.