Install the two files in:
Google Chrome/Contents/Versions/5.0.342.9/Google Chrome Framework.framework/Resources/

The file path may be a bit different depending on what version you have. Install it in the newest version folder there is.

April 18th 2010: Fixed a small visual bug that occurs when running an Incognito window. Please re-download if you are not running this current version.

Still not small enough? You can download this smaller version. [screenshot]

Like the toolbar icons? Download this beautiful UI mod by Jonas Rask.