UPDATE: According to FTWPodcast.com, CM Punk attended the Rancid show in Detroit, Michigan last night and appeared onstage with the band. During his appearance, lead singer Lars Frederiksen said he had written new music for Punk and it would debut at the WWE Payback PPV. Punk posted the following on Twitter…

Rock 'N Roll

ORIGINAL CM Punk attended a concert for the band Rancid on Tuesday night in Detroit. Before playing their new song, "F**k You", band member Lars Fredericksen called CM Punk on stage and joked that the song should be his new WWE entrance theme. They also got the crowd to chant, "..1..2..3..F**K YOU PHILLIP!!" at Punk.

If you're interested, you can click here to view photos of CM Punk on stage with Rancid at last night's (6/11) concert.