Comma are our friends

It seem to me that someone posted a sentence here that illustrates how a misplaced comma can completely change the meaning of a sentence. Could I have a rerun of that post? I couldn't find it by searching the archives.

I've been asked to help teach a class of insurance actuaries how to write well-organized and clearly written reports. Any examples of garbled bureaucratic writing, use of jargon, common mistakes, etc., or recommendations regarding good reference books would be appreciated. My subject title, by the way, is the title of such a book.

One example I remember vividly from a 4th grade filmstrip was "Let's eat, Grandma!" As a 9-year-old, I found the omission of the comma hilarious.