All businessman are crazy about the pie chart. Here is Pie3D powered by dojox.gfx3d. The interface for the end-user is pretty similar with dojox.chart.bar3d: just add the data via addSeries, set the light, then call render, boo, you are all set.
There is a long design struggle between dojox.gfx and dojox.gfx3d. The 3D pie chart is a Cylinder, but crippled intentionally, for example, only rotation around Y axis is supported. Last but not the least, it is much easier for user to specify the rx, ry and height, instead of scratching their heads to find the right rotation angle. dojox.gfx would suffice.
On the other hand, dojox.gfx3d brings schedulers and reusable gradient from Cylinder. The schedulers may be essential if we want to highlight some slices by moving them a little bit away from the center. Plan to throw one away; you will, anyhow. dojox.gfx3d is selected. Please checkout the code.