Mitch Joel over at Six Pixels of Separation posted a great reference today, pointing to a collection of cheat sheets and checklists for a myriad of different web marketing purposes, from design and coding references, to usability and SEO best practices: The Ultimate Digital Marketer's Reference.
Geeks everywhere should check out 30 Handy Cheat Sheets and Reference Guides for Web Professionals.
Thanks, Mitch.