What Are Your Favorite Keyboard Shortcuts?

At Giz, we spend our days all clickity-clackity on our keyboards, and we're pretty sure a lot of you sit at desks all day, too. Like us, you've probably got some favored keyboard shortcuts that changed your life when you discovered them. We want you to share it with us. What are the best keyboard shortcuts?

Now, I'm not talking about some amateur Command+C bull crap. I want the goods. I WANT TO OPTIMIZE. What are the hidden gems that I need to know about? Besides simple shortcuts, I'd also be interested in what secondary applications and shortcut-related tips you might have tucked away in your brain.

I'll round up the best responses from the discussion below in a later post. Give me your knowledge!

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