I have a very specific requirement that I can't find a charting library for. I need to show multiple stacked column or step-area charts on the same 3D axes to compare multiple periods of time to each other - for example, the y axis would show sales volume with regions stacked above each other, the x axis hours of the day and the z axis selected days to compare. In addition, I'd like the chart to be real 3D and draggable rather than a basic static isometric view.
There is an expensive Java library that may be able to do an isometric version of the chart I need called EasyCharts; it's visual quality isn't as good as I'd like. None of the Flash libraries I found (AnyChart, FusionCharts, XML/SWF Charts) can combine multiple stacked charts.