I have greyhounds. You've heard of greyhound gas? If I tried that somebody would lose an eye. Although with the gun control we have up here this could be a valid form of household defense.
We used to have a Cavalier King Charles Spaniel, we got him in the fall of 2003. We had a wicked early winter that year, snowdrifts piled up against the back patio door. So we puppy pad trained him rather than dumping that poor itty bitty ball of cuteness and fluff out in the cold snow. (If I knew then what I know now... *punt*) Anyway, the winter passed and he got really good at peeing on the pad near the backdoor. When he was big enough we shoveled an area for him to go outside. All was well, we stopped with the pads, no accidents. We patted ourselves on the back because we had such a GOOD boy... Then one day I walked into the kitchen to see him peeing DOWN THE HEAT VENT BESIDE THE BACKDOOR! Apparently it wasn't the first time either, *gag*. Good thing the basement wasn't finished below because we had to take out and clean several feet of ducting. But thankfully, he really was a smart dog. We trained him to paw a bell on a rope hung by the backdoor. When that broke he started pawing the chain lock at the front door. If we were all upstairs he'd scratch at the bathroom door (I bet we could have trained that dog to go in the toilet, if he could have reached!). I miss that little bugger, now I can't paint one corner of the bathroom door because it's got his scratch marks.