Actress Keira Knightley says she has a habit of experimenting with wacky nail paints in her spare time.
However the 29-year-old 'The Duchess' star said she avoids doing it during the filming of a movie, reported Hello magazine.
"During filming I am carefully made-up for weeks, so at the end of every film I love to go out and buy nail polish in the most absurd colours and paint my nails with them. Last time I chose yellow - which I don't recommend," Knightley said.
"I looked like I and nicotine-stained fingers. I won't repeat the yellow experience, but you can count on me to find an even crazier shade next time," she added.
