They could shut down your ad-sense account and withhold funds. They could shut down your youtube account, ban some of your videos, or fudge the metrics on them.

They could shut down your ad-sense account and withhold funds. They could shut down your youtube account, ban some of your videos, or fudge the metrics on them. They could reveal all your Google searches to the public. They could lockup their apis' connections to your app. They could have #1 result on your name lead to a libelous page, either fake or real. They could modify or delete your emails. They could stop delivering emails or YT messages if they wanted to break a relationship. They could sell your personal data. They could use an auto-update of Chrome to send browsing or videocam and microphone data back to HQ - an update only sent to you. They could place a keylogger in only your Chrome and get your bank login, or have it navigate to a site without you knowing in a hidden window. They could find out when you're using Google finance, and insert fake numbers about your watchlist or portofolio. They could make all your websites in Webmaster Tools have PR of 0 or stop crawling it. They could return skewed search results. These aren't the only ways: think blackmail, identity theft, misinformation, impersonation. If they ruin your life, they will also be ruining or affecting other people's as well - the people connected to you.