Google has expanded the personalized search "field trial" it initiated last year, pulling in additional results from Google Calendar. Your Google Calendar appointments join your Gmail and Google Drive documents alongside traditional Google search results for an all-in-one Google search experience.
If you'd like to participate, head on over to the signup page and add your account.
Once that's done, just log in to your Google account. You'll then be able to search Gmail, your Google Drive documents and now your Google Calendar appointments directly from the Google search page (or from within Gmail).
The Google Calendar integration doesn't just add appointments, it also features support for natural language queries. For example, type "what is on my calendar today" and you'll see the day's agenda. More specific queries work as well; to find out when you're meeting someone, just type "when am I meeting" and the person's name.
Note that the personalized search trial is still only available to U.S. users with @gmail.com addresses (Google Apps accounts are out of luck for now). If you opt in and decide you hate it, you can always go back to the sign up page and turn universal search off.
