  One of the best things about geometry is that it's cool! Geometry enables us
to create incredible designs and astounding patterns. This article shows how to
use a simple technique (iteration) to create designs that are both cool and
introduce important mathematical concepts. We give examples using one of the
most common of geometrical constructions, namely, the similar triangle. In the
final section, we suggest other possibilities that could be used for guided
exploration or for student projects.
