8. Rihanna
Quickly shedding her innocent girl from Barbados act, Rihanna set the stage for Lady Gaga and Nicki Minaj (who was pretty close to making this list as well) in the mid-to-late 2000s, making avant-garde stage costumes and high concept fashion spreads a requirement for A-list female pop stardom. On a broader level, she’s had a bigger impact on women’s hair than anyone since Jennifer Aniston.