Search Engine Land has produced a very useful "Periodic Table" for search engine optimization ranking factors. This is a great at-a-glance graphic which can help anyone involved with SEO the opportunities, dangers, and housekeeping required to produce and maintain superior SERPs in the face of tough and determined competition. It's also fun to look at and impress your coworkers when you post it on a wall.
See the article on this SEO infographic at http://searchengineland.com/seotable. You can download the .pdf version here, and look at the complete graphic.