POPSUGAR Celebrity John Mayer Slide Photo of John Mayer Performing at Hard Rock Cafe London Rock Out by Celebrity 1/12/10 0 Shares Like us on Facebook Sign up for our daily newsletter > John Mayer performed at the Hard Rock Cafe in London on Monday. Image Source: WireImage Read More HotJohn Mayer John Mayer The Most Surprising Celebrity Sex Confessions Katy Perry and John Mayer Break Up . . . Again Personal Trainer to the Stars Harley Pasternak Shares His Secrets John Mayer Dreams Up Justin's Cookie Dough Almond Butter POPSUGAR, the #1 independent media and technology company for women. Where more than 75 million women go for original, inspirational content that feeds their passions and interests. Be in the Know With OurCelebrity and Entertainment Newsletter Personalize TV Movies Young Hollywood A-Listers Sign up with facebook or By signing up, I agree to the Terms and to receive emails from POPSUGAR.