I am a developer. But I am also an avid user of web sites and web applications. And as a user, I happen to really like the applications put out by Google. In particular, I like how they keep things simple, clean and uncluttered. And they don't get side tracked adding features and frills that impress everyone except the actual user of the application.
Then I found this on Google's web site, Ten principles that contribute to a Googley user experience, that summarizes their design philosophies.
I also like the apps by 37signals, specifically: BaseCamp and Highrise. As luck would have it, 37signals also has a web site explaining their UX and development philosophies called Getting Real.