If your preferred Search Engine is Google, and your browser accepts its cookie, you should give some thought to the consequence, both good and potentially bad : this page tries to help you do that, together with an easy way to anonymize it without missing out on its benefits.
First the good. It's useful to you. It's how Google saves your preferences (such as language, filtering, number of results per page, etc). If, like me, you want a hundred results per page (not just ten), in English only (not in languages I can't read), unfiltered for adult content (I'm not a child), then you need the Google cookie.

Now the potentially bad. You use Google a lot, right? If someone was peering over your shoulder, watching every Google search you made; making a note of what you looked for; what you found; and sometimes where you visited from the results; (and maybe every email you sent and received); and did so for years and years: they'd grow to know quite a bit about you, eh? Well, that's what the cookie allows Google to do, forever, if you don't take simple precautions.

You can read more on all that below, if you like. Here are a couple of simple, hassle-free precautions.

• Use this simple GoogleAnon bookmarklet to anonymize your Google cookie. Right-Click Here GoogleAnon to be replaced and save as a favorite or bookmark (or drag it [v.] to your Links/Personal bar).

When you click it your Google GUID will be reset to all zeroes - all the while automatically keeping your saved preferences (such as language, filtering, number of results, etc).Notes :

• It should work for, at least, IE4+, Opera, Mozilla and Firefox.
• Click it while still viewing a Google page (either the main Google.com site or any of the country domains like Google.ca or Google.co.uk : it won't work while viewing other sites.
• You need to have your browser set to accept cookies, of course, and not have Proxomitron or a similar tool mangling the javascript too much.
• You may get a security warning because they contain javascript: if you like you can check the page code before you download them (right-click/view source or file/edit...), or before using them (right-click/properties).
• For the latest versions/patches of IE you may need to add the site to your Trusted Zone to enable drag'n'drop. You shouldn't be adding Bookmarklets from a site you don't trust anyway, but if in doubt don't use the drag'n'drop method, or remove the site from the Trusted Zone afterwards.
• Click it again whenever you change your Google preferences, or you flush your cookies and thus get a new one from Google.You can use this one : ShowCookie to view your Google cookie (or any cookie set by any site). For Google, the first number is your GUID (all zeroes is goodOr :-
• Flush your cookies frequently, or every so often. Here's how for IE, Opera, Mozilla, Firefox, or use a cookie manager.