You know and love the South End's Beehive: Now meet the hippie-inspired Beat Hotel, their sister restaurant in Harvard Square that recalls the neighborhood of yore, a hangout for restless spirits like Allen Ginsberg, William Burroughs, and Edie Sedgwick. The bar-brasserie-live music venue opens tonight at 5 p.m., a rep tells us. Expect a "wholesome" menu with plenty of veggie options, small-batch wines, and a roster of live blues, world music, and jazz. Their mission is to satisfy residents and "vagabonds passing through." We're intrigued. The restaurant is at 13 Brattle St.