Exporting 3D to After Effects
When you create a grid box inside Vanishing Point, in addition to having the option of returning that grid back to Photoshop as a 3D object, you also have the option of exporting it as a 3D object that you can import into After Effects CS3 and manipulate in a 3D layer. Just click on the small right-facing triangle in the top of the dialog and in the flyout menu, choose Export for After Effects CS3 (.vpe).