I just found a company that has been formed and is creating anew coaster model construction kit that can be put together using flexible track however you see fit. To bad I don't have an extra $500 put aside to reserve mine. It's pretty kick a** though. You can check out a video and photos here http://www.coasterdynamix.com/products.aspx
I wasn't sure where to post this so sorry if this is the inappropriate place.