Jimi Hendrix opened for The Monkees on their 1967 tour, and it did not go well. The young, mostly female crowd shouted "Davy" when Hendrix sang the word "Lady" in "Foxy Lady" in honor of who they came to see: Monkees lead singer Davy Jones.
Eddie Vedder often changes the words when he sings "Yellow Ledbetter." The basic story is about a guy whose brother dies in the first Gulf War. Apparently, bad news in the army is given in yellow envelopes.