The worst offense my dog has ever committed was nibbling up part of a photo frame and scratching maniacally at the edge of a cabinet (we're still sanding it down). But from what I've heard from other pet-owning friends, I've gotten off pretty easily in comparison to some of the horrors their pets have committed against their home decor.
One of my favorite designers, David Trubridge, posted this photo on his Facebook page, explaining, "A very upset customer from Australia contacted me last year. She was assembling her Floral and left the room for 30 seconds, when she came back she found this! Some pieces were destroyed but we sent her some more in exchange for the photo!"