My friend put his cat on a leash outside while he went to the convenience store. When he came back, the cat was gone. 3 hours later we found him. He had escaped the leash, climbed a tree, and jumped onto the roof of the house and couldn't get down.

Few years ago, while walking my dog, we passed a house that had a Parrot sitting on its porch. My dog was terrified of this bird and escaped his leash. Had to chase him down 3 blocks, but rescued him in the end. He doesnt like birds to this day.