My affection for this song isn't for the studio version-that's rightly a classic, though-but rather, the live versions from 1971-1972 or so, where Zeppelin turned it into a vehicle for a medley of pop, rock, and blues numbers, sometimes stretching it out to around 30 minutes in length. Early Zep had numbers in their set-As Long As I Have You, How Many More Times, Whole Lotta Love-where the band would just relentlessly smash through medleys, making the songs their own while still keeping something of their familiar structures. That started going away as No Quarter, Dazed And Confused, and Moby Dick started taking up upwards to 90 minutes of the set, but there's a lot of fun to be had in the live versions of Whole Lotta Love when it had medleys embedded in it.