Those announcements have become as much a regular feature of theatergoing as ushers and Playbills. And how to ask patrons to turn off anything that beeps or glows is often the subject of serious consideration by directors, producers and sound designers, whether they choose a standard version (delivered by stage managers, recorded or live) or a humorous one, like Angela Lansbury’s exaggerated formal instructions before “Night Music.”
via nytimes.com
It's just a matter of time till I'm one of the offenders. Still, some pretty interesting strategies are discussed in the full post.