I have seen a few of these launchers. My issue is the footprint, they are usually ugly, and not very customizable.
I would love to see someone make one with DX that you could choose the icons you wanted to use. Something like this.
Each arrow would rotate a different set of icons/folders/apps as it were. But they would all rotate through under one window, insted of a large segmented, circular window with all of them showing. Maybe even a switch that directs it to what you want to look for. Like folders, apps, docs, pics, etc.