19. Cameron Diaz and Drew Barrymore
The Charlie's Angels costars met and struck up a casual friendship as teenagers, but didn't become true BFFs until they paired up for the 2002 action flick. Barrymore and Diaz frequently take to social media (sometimes sans makeup!) to update us on their friendship, including cooking classes and girls' nights in. Barrymore was a bridesmaid for Diaz in 2015 and Diaz supported her pal through her divorce in 2016. These two clearly share a kickass friendship both on and off screen.