The blues standard "Smokestack Lightnin'" is song made famous by Howlin' Wolf in 1956. Since then, dozens of performers covered it; but another blues legend, Muddy Waters, did his own cover too.
The song is a lot more laid back, feauturing Muddy's hypnotic late 50's sound. Some of the lyrics are altered as well, and the famous opening line and verse of the original was moved to the third verse.
Interesting take on this song... most bluesmen covered each others' songs over the years.
Here it is: