In an age when left-of-center lady-rock started flourishing (like that of Tori Amos, who eschewed plucking guitars in favor of tickling ivories), the premise of a cello-centric rock ensemble wasn't terribly farfetched. And from that germ of an idea, eventually Rasputina formed, a rock band that slyly avoided constraints of a single genre and found itself winning admirers everywhere -- even goth rock stalwarts like Marilyn Manson. Despite a constant revolving door of collaborators, the spirit of Rasputina remains sure-footed as ever, with Melora Creager still at the helm. And although Rasputina's next album won't surface for awhile, this Sunday marks a one-off recital at Williamsburg's Knitting Factory, where the setlist has already been pieced together by song requests e-mailed by fans. However, motherhood -- Creager is pregnant with her second child and has been combing through her wardrobe trying to figure out attire for the show accordingly -- hasn't mellowed her in the least.