ColorZilla is another very simple FireFox add-on that allows you to quickly get information about colors used on a webpage without having to leave your browser. After you install the add-on, you will see a small icon in the lower left hand corner of your browser:

When you click on the icon, the cursor will turn into a crosshair icon and information will show up at the bottom of the window for the color the mouse is currently over. Clicking the button will go back to a normal cursor and the color information for the clicked area will be kept in the status bar:

Right clicking the icon will bring up helpful options for copying your color information to the clipboard:

That's it. Another super simple time saver!