Because it's funny, here's my embarrassing clothing malfunction:
Once at work, I walked down a loooong hallway to speak to the boss. I had just stepped into his office when a female coworker scurried up and whispered in my ear "You just had a pair of underwear fall out of your pants!"
Apparently it had gotten stuck in my pant leg and they'd gone through the wash together, and gotten dislodged and fell out while I walked around the office. I'm afraid I was terribly embarrassed, babbled a little and quickly tossed them in the bathroom trashcan because I didn't want to walk down the hall carrying a pair of panties.
So, so, so glad they didn't fall out once I got into my boss's office. And that one of the coworkers who saw the incident told me quickly and discreetly.