Each Google Chrome installation contains a unique ID that identifies its user. Google doesn’t make it an easy job to remove this ID. If you have privacy concerns and want to make your Google Chrome installation truly anonymous, here is a tool that does the job for you.

UnChrome replaces your unique ID with Null values so that your browser can no longer be identified. The functionality of Google Chrome is not affected by this.
Close all instances of your Chrome browser, and run UnChrome. When it has successfully completed its job, you can delete this UnChrome file. No need to save it, since it needs only be run once. You will remain anonymous through upgrades to Chrome.
UnChrome may be used with Windows 7, Windows Vista, Windows XP and supports all 32 an 64-Bit versions of Windows. UnChrome is freeware, but is an ad-supported tool.
Home Page: UnChrome.
Chrome Privacy Protector and Chrome Privacy Guard is another such similar tool you might want to have a look at.

You can also manually edit the Local State file where this Unique User ID is stored. You can typically find it here:
C:\Users\Username\Local Settings\Application Data\Google\Chrome\User Data
Open it with a text editor. Locate a line starting with “client_id” and change it to FA7069F6-ACF8-4E92-805E-2AEBC67F45E0. This is the client ID used by the portable Chrome browser.
UPDATE: Information on this was supposed to be available here at Google. But that link is broken. Maybe Google decided to remove client_id, I’m not aware. If any Chrome user has information about it, please do share in the comments.
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