Linkage
Don't know why your's didn't come through. You can always just enclose the URL in brackets. Nice picture, I'll add that to my possible designs next time I'm at the beach. It looks like a pretty simple design. The really good ones have five fold symmetry, three and six fold symmetries are easy to create with just making arcs.
http://www.news.com.au/adelaidenow/gallery/0,22613,5032781-17382,00.html#