Rihanna -- Shines Bright Like a Blonde!

Even with no signs of her d-bag ex Chris Brown, Rihanna still wigged out in New York City last night.

The sexy 25-year-old pop diva showed off her new interesting look ... by rockin' a synthetic platinum Ann Jillian 'do as she arrived to her Manhattan hotel on Monday. Doesn't it just make you want to throw up?

Now that she and Chris have broken up for the time being, Rihanna is going to prove that blondes have a lot more fun.