We are working on a bridge so users can create layouts similar to below pictures. The bridge is better suited for our new one piece tiles found at link below, but can be used for the original 30cm tiles as well.
http://tinyrc.com/forums/showthread.php?t=24515
The bridge will be made of EVA foam and will go together quickly. The height of the bridge will be better suited for 2.4 frequency cars with no antenna, but can be used with mini-z's' and other small scale RC cars with antenna's. Slight modifications to the antenna would be recommended by just bending it down a little, so it clears the bridge.