What is the most embarrassing thing to ever happen to you -- either professionally or personally?

Serena Williams, tennis champion: Just the other day, at a very big event, I had a very low dress on, and it, um, kind of fell.

	Marcellus Wiley talks to NFL rookies on how to escape from veteran tape attacks.

Marcellus Wiley, San Diego Chargers defensive end: On the field, it was when Eddie George flattened me. It was my first game coming back from a back surgery, and I had "camel legs." And Eddie George decided he wanted to chip-block on me on the third play of the game. It was our first televised game with me as the starter in Buffalo -- Sunday night on ESPN. And they replayed that something like 88 times. I got kaboomed! Off the field, Ted Washington and Bruce Smith taped me up as a rookie. That wasn't fun, but luckily, I just got taped and wrestled down and kind of choked. I had some respiratory issues that day. Pat Williams, on the other hand, he got taped and was laying there naked for an hour and a half. And we all took showers and all walked over him. And it was bad because he didn't talk to us for like a week.

Kato Kaelin, actor, comedian, former O.J. Simpson houseguest: Well, honestly, I'm a bed-wetter, and it's the worst thing. Even to this day, I still do it -- but now I do it from the hallway.

Tony Gonzalez, Kansas City Chiefs tight end: One time I had to pee during a game. It wasn't too embarrassing though. I peed right there on the sideline. I just knelt down and put a little towel in front of me. Everyone was looking at me, though.

Julius Erving, Pro Basketball Hall of Famer: Probably some game somewhere, sometime, having an uncontested dunk and missing it. Especially when you are trying to really throw it down hard. Seeing the ball hit the back of the rim and shooting out. I don't remember it happening often but it did happen.

Lisa Leslie, Los Angeles Sparks center: Getting my swimsuit bra snapped off in the pool in front of a lot of people. I was playing basketball in the pool with some people I didn't know. This guy was guarding me, and it just snapped right off.

George Lopez, actor and comedian: One time I was doing a show at this amphitheater with about 6,500 people, and my fly was down. This guy in the front row said "Hey, man, your zipper is down."

Roselyn Sanchez, actress: I was doing a film once. It was my first English job. I was supposed to cry, and we only had one take. I was so nervous that if I didn't cry they would fire me. I was backstage cutting onions. I still didn't cry. Everybody was laughing at me.

Summer Sanders, host of "NBA Inside Stuff" and Olympic gold medalist in swimming: I once invented a word on "Good Morning America." I made up a word called "comfortability," which really should be a word.