What techniques do you know\use to create user-friendly GUI ?

I can name following techniques that I find especially useful:

• Non-blocking notifications (floating dialogs like in Firefox3 or Vista's pop-up messages in tray area)
• Absence of "Save" button
  MS OneNote as an example.
  IM clients can save conversation history automatically
• Integrated search
  Search not only through help files but rather make UI elements searchable.
  Vista made a good step toward such GUI.
  Scout addin Microsoft Office was a really great idea.
• Context oriented UI (Ribbon bar in MS Office 2007)

Do you implement something like listed techniques in your software?

Edit:
As Ryan P mentioned, one of the best way to create usable app is to put yourself in user's place. I totally agree with it, but what I want to see in this topic is specific techniques (like those I mentioned above) rather than general recommendations.