I Don't Think You Need All of Those at the end of Your Sentence There...

"I suppose the only rule is: only use an exclamation mark when you are absolutely sure you require such a big effect... 'an excessive use of exclamation marks is a certain indication of an unpractised writer or of one who wants to add a spurious dash of sensation to something unsensational'" (Truss 138-139).

I know I personally only use an exclamation point when I'm writing dialog and a character is either extremely surprised or extremely angry (and sometimes a character is a little of both.)  I don't go throwing around exclamation points in my papers, as it would be extremely out of place to throw in one at the end of sentence like "There is foreshadowing in 'A Good Man is Hard to Find'!"  The reader would be taken aback and I would assume they would be thinking "Alright! I get the point.  There's foreshadowing in the story. You don't have to yell at me", which I know is what I associate exclamation points with.  H.W. Fowler (the quote within the quote) is right: you should never use too many exclamation points.

Except, you know, when you're making fun of other people using too many exclamation points, which I have been known to do out in cyberworld.