Activate extension via short cut key - Stack Overflow

UPDATE (5/24/2013): You can use the new chrome.commands API, which provides built-in framework support for keyboard commands.

Original answer follows:

Step 1: Use a content script to bind a keypress listener to every page.

// in the content script, listen for Crtl+Shift+E (upper or lowercase)  document.documentElement.addEventListener("keypress", function(event) {      if((e.keyCode == 69 || e.keyCode == 101) && e.ctrlKey && e.shiftKey) {          // do something (step 2, below)      }  }, true);  

Step 2: For action outside of the content script, use message passing to notify the background page that the shortcut key has been pressed and it should perform some action.

Step 3: The background page does some action. It's currently not possible (and will likely never be possible) to open a Browser Action popup programatically, but you could send an interactive desktop notification, open a new tab, or do a lot of other things.

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