Now there’s a bang! Mayim Bialik, 38, is the perfect balance of practical and prepared. “I’m not a fancy person,” admits The Big Bang Theory actress. “I’ve had this Army surplus bag since high school!” What does the mom of Miles, 8, and Frederick, 6, (with ex Michael Stone) carry around in her purse? Mayim spills her must have essentials just for Us Weekly.

Small Fortune

“I use a Chinese satin jewelry roll as a wallet. I got it in Chinatown in L.A. It’s so tiny I need to fold my bills in thirds to fit.”

Teen Choice

“Votre Vu in Claire is my favorite lipstick. It reminds me of the bronzy Clinique shade I was first allowed to wear in junior high.”

Write of Passage

“When I was 16, the creator of Blossom gave me a Montblanc pen and said, ‘Don’t treat this pen special. Throw it in your bag and it’ll last forever.’ I always use it.”

Mind the Gap

“Yes, I still wear a retainer — just not when filming.”

Liftoff luck

“I’m jewish, so I sometimes carry an ArtScroll prayer book. I also have a copy of the traveler’s prayer slipped in the back of my phone case. When I’m on a plane I say it to wish myself safety.”