Cell Phone ettiquette

The other day in class, a little tune started to play. My flustered student rummaged in her bag, but it wasn't her cell phone going off. It was her computer! Even though it was closed, somehow it had turned itself on and was playing a tune. We all ended up trying to help her figure out how to turn it off, because none of us knew why it was happening: was it an alarm she'd set accidentally? a ghost? we finally shut it down and had a good laugh, but it reminded me of a post I'd recently seen about Cell phone etiquette. We all have our pet peeves!
Ever wanted to tell someone to get off the phone during a concert? Here are two versions of how to do it.