Salem did two years ago, actually!
I was out of town and my dad was watching him. While I was gone he contracted a virus and had diarrhea and was vomiting. My dad stumbled onto the mess and began to clean it, opening the window to air the area out. A few minutes later Salem felt sick again, so he jumped out the window and through the screen (about 2.5 feet off of the ground) and fell about 4 feet to the ground outside (thank goodness we have a one story house!) and then went in to do his business.
My dad took him to the vet to get checked out and the vet told him that we have a very smart boy on our hands! :P
He is your friend, your partner, your defender, your friend. You are his life, his love, his leader. He will be yours, faithful and true, to the last beat of his heart. You owe it to him to be worthy of such devotion. - Unknown