Rihanna Topless on Beach -- Watch It All Fall Out

Rihanna blew her top again yesterday -- and this time, the singer stripped down to just her bikini bottoms on the beach in Brazil ... in front of lots and lots of people.

Rihanna wasn't just getting naked for fun though -- not like she's opposed to it -- she was posing in a fashion shoot for Vogue magazine, which apparently continues to do God's work. Keep it up, folks.

Gotta love Brazil ... or as we like to call it, NO BRA-zil.