In the attention-span showdown between the big screen and every other screen — your computer monitor at work, your flat panel at home, the little glass teat in your hip pocket — the place where you queue up to watch a movie in hamthrax-passing proximity to strangers looks to be on its way out. But hang on. You weren't really going to wait for Blu-ray to see Star Trek lens-flare its way back onto a 50-foot bolt of industrial-grade polyester, were you? No, not when hometown-headquartered AMC's new downtown theater, the Mainstreet, was opening just in time to launch the Enterprise this past May. The 88-year-old building, once a vaudeville hall and later a Cinerama palace, embraces its old-school, movie-movie legacy: Instead of a multiplex maze, the boutique Mainstreet holds just six auditoriums, half of which seat fewer than 50 people. The screens are wide, and so are the berths, with buttery-soft reserved seats (wired to jolt you when the movie action kicks in) and, in those three smaller rooms, fold-up trays and full food-and-drink service. The Marquee Bar & Grill, with its on-and-on-till-the-break-of-dawn menu and cushy appointing, is just a bonus. Because look, the deal is that now this city has two kinds of movie houses: the kind that shake you a drink and then shake your ass and the kind that don't. Live long and prosper, Mainstreet.