The Freddie Mercury Tribute with Queen back in '92 had quite an array of vocalists- the rundown is here:
en.wikipedia.org/wiki/The_Freddie_Mercury_Tribute_ConcertThe acts that played
with Queen:
1. Queen + Joe Elliott/Slash - "Tie Your Mother Down"
2. Queen + Roger Daltrey/Tony Iommi - "Heaven and Hell" (intro), "Pinball Wizard" (intro), "I Want It All"
3. Queen + Zucchero - "Las Palabras de Amor"
4. Queen + Gary Cherone/Tony Iommi - "Hammer to Fall"
5. Queen + James Hetfield/Tony Iommi - "Stone Cold Crazy "
6. Queen + Robert Plant - "Innuendo", "Thank You" (intro), "Crazy Little Thing Called Love"
7. Brian May with Spike Edney - "Too Much Love Will Kill You"
8. Queen + Paul Young - "Radio Ga Ga"
9. Queen + Seal - "Who Wants to Live Forever"
10. Queen + Lisa Stansfield - "I Want to Break Free"
11. Queen + David Bowie/Annie Lennox - "Under Pressure"
12. Queen + Ian Hunter/David Bowie/Mick Ronson/Joe Elliot/Phil Collen - "All The Young Dudes"
13. Queen + David Bowie/Mick Ronson - "Heroes"
14. David Bowie - "The Lord's Prayer"
15. Queen + George Michael - "'39"
16. Queen + George Michael/Lisa Stansfield - "These Are the Days of Our Lives"
17. Queen + George Michael - "Somebody to Love"
18. Queen + Elton John/Axl Rose - "Bohemian Rhapsody"
19. Queen + Elton John/Tony Iommi - "The Show Must Go On"
20. Queen + Axl Rose - "We Will Rock You"
21. Queen + Liza Minnelli/Cast - "We Are the Champions"
22. Queen - God Save The Queen (taped outro)