The nuns at the Beit Jimal monastary in Israel sang R' Chaim Banet's "Avinu Av Harachaman" as part of their Christmas services.
Here's the video:
אבינו אב הרחמן של ר' חיים בנט במיסת חג המולד בבית גמאל from bhol on Vimeo.
More commentary on this at Life in Israel, where I found this.
