P!nk's rock-laced, blockbuster hip-pop is so densely eclectic, it's not surprising to hear it echoed in myriad contemporaries' work. You can spot her confessional bent and zeal for self-empowerment in the huge-voiced balladry of Adele and Kelly Clarkson, while her party-starting, dance-floor-shaking firebrand pop can be heard in Rihanna's sultry anthems and Katy Perry's bubblegum confections.