Last year my dad had to put his wolf/lab to sleep because she became too unpredictable, and she ripped his hand open. She was a smart dog, great fun to play with, but she was way to wild, and getting dangerous.
And, my moms dog that was a mix of Chihuahua, Pekanese, Yorkshire, and Poodle died after 13 years from heart failure. She was possibly the smartest dog I've ever seen. She wouldn't just do normal tricks like roll over. She could turn around, and then roll over, or she could go get 1 of 10 different toys laid out on command. She started shaking her head "no" about 4 years ago. You could ask her "You want to go out?" She'd start barking and swinging her head left and right....fuckin amazing dog. She knew when you said "Want to be held?" "Want food?" and she'd either bark and stomp her front feet or swing her head in a "no" motion.
They have a new dog now. Muffin.....and she's got some anxiety issues but shes ok... Not real smart. No real tricks other than getting on the table when no one is looking and eating everones lunch.
I hope to get a Weimaraner next summer. I'm kind of hesitent as I know that one day she'll die. I've been through 4 dogs and 2 cats in my life that I liked, and it can get tough when you get so attached to them.