Budgets for cultural organizations are down, but a dazzling performing arts center is rising across from City Hall. Over the years, we have watched a symphony orchestra pull off a remarkable resurrection and an opera company go belly up. Arts groups wounded by the economic downturn and corporate funding cutbacks have been forced to go leaner in order to keep presenting their concerts, performances and exhibits. Individual artists, meanwhile, continue to branch out, not limiting their creations to a traditional stage or a gallery, but rather seeking unlikely venues like a rooftop or even an old motel-turned-arts-haven.