Attached Link: http://www3.corel.com/cgi-bin/gx.cgi/AppLogic+FTContentServer?pagename=Corel/Product/Details&id=CC1

I can't think of a 3D program to do that easily, but I can recommend Corel's KnockOut program which is basically a masking program used for post production work. It allows you to make selection masks that preserve their transparencies too. It is a bit tricky to get use to at first, but it can produce some very stunning results. It's great to make masks for hair too. You can check it out at: http://www3.corel.com/cgi-bin/gx.cgi/AppLogic+FTContentServer?pagename=Corel/Product/Details&id=CC1OXMK03AC visualkinetics