AGE: 27
OCCUPATION: Pop star, TMZ mainstay
PREVIOUS APPEARANCES ON THE TIME 100: 0
PRO: Her on-again, off-again affair with lucidity appears to be on the upswing, allowing her to tour for the first time in five years and to film a wobbly yet charming turn on How I Met Your Mother.
CON: Her newfound stability is likely because of a conservatorship deal she signed last year, which won't even let her flip off a barista without legal supervision.