When I was dog sitting my friend Ana's White Shepherd, I noticed a strange habit Ana had described to me when I first met Nacho. He was literally obsessed with water.
As much as I tried to get him to stop, Nacho believed that the water was going to up and prance out of his reach. So when he drank, he drank. Like a freshman at their first college party, he didn't know his limit. And he peed. Oh, did he pee. Accidents, frequent trips out and nighttime whining sessions were all regular for Nacho.
Until now, I didn't know of any other dogs doing this, or why Nacho did it. Finally, THAT MUTT (another great dog blog) posted an anecdote about it. According to vets, it's dog OCD (unless the dog doesn't usually behave this way -- then it means it might be sick, so take it to the vet immediately). Again, I learn something new every day. Thanks to Lindsay Stordahl for the info.