A Mathematician's Aesthetics http://m759.freeservers.com/PHaesthetics.html
In his classic A Mathematician's Apology, G. H. Hardy likened mathematics to poetry and painting. This site elaborates on Hardy's remark with quotations from Stevens, Klee, Fry, and Focillon. Links to related sites are given.
Math Cats http://www.mathcats.com/
A magic chalkboard takes you to a math art gallery and lots of interactive math activities, including: magic squares, conversions, seasonal surveys, symmetry, tessellations, geometric designs, games.