Slow walking Walter, the fire engine guy.

The story:

My friend was telling me a story about how his parents shocked him one day by nodding their heads with the beat as the intro to Smoke on the Water played. He almost wizzed himself laughing when they both came out with "Slow walking Walter, the fire engine guy" when the chorus came around. They had been singing that line for 30 years. I guess nobody had the heart to tell them. (or they were laughing to hard at the time.) haha