We introduce and prove some basic results about a combinatorial model which
produces embedded polygons in the plane. The model is closely related to outer
billiards on kites, and also is related to corner percolation, to Hooper's
Truchet tile system, to self-similar tilings, and to polyhedron exchange
transformations.Comment: 68 pages. This is an more polished version of the original
submission. The connection to polytope exchanges is developed and one of the
speculative sections has been eliminated. Otherwise, it has the same result