First, there’s an article by Luke Wroblewski about the importance of considering mobile devices first for websites and web applications.
Ethan Marcotte describes foundations and some techniques of responsive web design.
An article by James Young deals with ‘the top responsive web design problems and how to avoid them‘
Brad Frost wrote about responsive navigation patterns, e.g. how to implement a website navigation that works seamlessly on both desktop and mobile / small screen / touch devices.