Ten Principles of Good Design by Dieter Rams
Dieter Rams once asked himself if his design was good. A simple but insightful question. Soon afterward he came up with a sort of checklist of commandments that is still of use today.
By the way, am I the only one who thinks the new WordPress makes it really difficult to post in such a tiny box. Also uploading photos was a lot easier when we could dump all the photos in at once.