I started keeping a list of what Google knows about me. Even knowing full well that I gave this information to Google freely, it’s pretty awe inspiring.

• Google knows every website I’ve ever visited (Chrome)
• Google knows who all my friends are (Gmail)
• Google knows who my closest friends are (Gchat, Gmail)
• Google knows what products I’ve purchased and how much I’ve spent (Gmail receipts)
• Google knows what mailing lists I’m subscribed to, and to which clubs I belong (Google Groups, Gmail)
• Google knows what stocks I own (Google Finance)
• Google knows how popular my websites are, and, by proxy, how well my startup is going (Google Analytics)
• Google knows where I travel and when I am traveling (Google Maps, Google Maps on iPhone)
• Google knows what I look like and what my friends look like (Picasa)
• Google knows where I am during the day, and who I’m with, and for what purpose (Google Calendar)
• Google knows intimate details about my work and personal projects (Google Docs)

Obviously it’s an algorithm, and there isn’t a dude sitting at a computer in Palo Alto learning everything about me. But if someone wanted to, they would have a pretty easy time of invading my privacy to an insane degree.

We put a lot of trust in Google to handle our information on a day to day basis. There’s no grander point here, just something to think about. And I’m glad at least I can always walk away from Google if I wanted to.