Even the greatest musicians need an extra hand sometimes. Whether it's a sizzling guitar solo or some sweet background harmonies, having a special guest musician can take a good song and make it great. This week we're discussing artists who have not merely butted into another musician's songs but have made the song better in the process.

SHOW NOTES

• "While My Guitar Gently Weeps" by the Beatles featuring Eric Clapton (Joint Choice)
• "(Nothing But) Flowers" by the Talking Heads featuring Johnny Marr (Richard's Choice)
• "No One Knows" by the Queens of the Stone Age featuring Dave Grohl (Michael's Choice)
• "Fairytale of New York" by the Pogues featuring Kirsty MacColl (Richard's Choice)
• "Gossip Folks" by Missy Elliot featuring Ludacris (Michael's Choice)
• "Groove Is in the Heart" by Dee-Lite featuring Bootsy Collins (Richard's Choice)
• "Shiny Happy People" by R.E.M. featuring Kate Pierson (Michael's Choice)