If you save the geometry you create in the Adobe 3D Toolkit 8.1 as U3D and choose 'U3D ECMA Version 1.0' under settings in the 'File > Save As' dialogue, you can then convert the U3D file to PDF or embed it in a PDF using Acrobat 3D and anyone with Reader 7.0 or high will be able to open the file.If you save as U3D Ecma 3.0, it will require Reader 8.1 or higher.
Jim Merry, VP 3D PDF, Tetra 4D, jim [dot] merry [at] tetra4d [dot] com
Jim Merry, VP 3D PDF, Tetra 4D, jim [dot] merry [at] tetra4d [dot] com