['I was told by a co-worker the other day that my fly was open.  Appearantly I had been walking around for half the day with an open fly.  My face sure was red.', "I can imagine how embarrassing that must have been.  I hope you didn't have to give a speech today.", 'I actually was supposed to give one later on that day at work.  I am glad I was told before the presentation!']
Whew. Certainly must appreciate your co-workers candidness.  It happens to all of us.
I was at work recently and had an interesting thing occur.  About halfway through the day, one of my buddies came over to my desk and told me my fly was undone.  I had been walking around all day with an open fly