Arp 81 is a strongly interacting pair of galaxies, seen about 100 million years after their closest approach. It consists of NGC 6621 (to the left) and NGC 6622 (to the right). NGC 6621 is the larger of the two, and is a very disturbed spiral galaxy.
Pretty cool images from the Hubble Space Telescope of various colliding galaxies . If you haven't seen the Hubblecast vidcast, I highly recommend it.