X marked the spot all weekend at 7th and Montana as a team of skywriters repeatedly circled the airspace over Our Favorite Starbucks, leaving a stream of Xes in their wake. At first, I wasn't sure what to make of it. Was someone marking our neighborhood as a warning ("Keep your distance ... you're entering unpredictable local loon territory!")? Or was it a UFO alert ("Danger: Unidentified Fritters Onsite!")? It turns out it was none of the above. Twentieth Century Fox was behind the whole thing: It was a teaser campaign for the latest X-Men movie. X-Men: First Class hits theaters on Friday.