By Leah Greenblatt
Updated June 01, 2010 at 06:05 PM EDT

Image Credit: Janet Mayer/PR Photos; Kent Miller/PR PhotosFans at a Daughtry concert in Nashville this weekend were treated to a surprise drop-in from OG Idol winner Kelly Clarkson, who came on stage to perform a sit-down acoustic duet with season-five fourth-place finisher Chris Daughtry.

The song they performed? No“No Boundaries” for these kids; instead, the pair took on Tracy Chapman’s ruminative 1988 dream-of-a-better-life ballad “Fast Car”:

As our own Idol dreamer Michale Slezak posited today in an EW staff email, could this possibly be the jump-off for an AI alumni duets album? I feel like Taylor Hicks might be available.

Is Monsieur Slezak on to something? Give us your picks for pairings (and why not, song choices) in the comments section below.

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