I recently jumped into one of the challenges over at ArtOrder.blogspot.com. The objective was to design a character starting with silhouette, go to detail, then color, and ultimately work up to a book cover, using a provided template. The specifics and requirements of the challenge are here: http://artorder.blogspot.com/2009/09/new-challenge.html
The character being addressed is the Mayan god of wind, storm, and fire: Hurakan.
And off we go!