Teresa Nielsen Hayden dissects bad advice on cover letters. I mention this here not because I submit cover letters for manuscripts, or because I think many of my readers will, but because it includes this instant messaging exchange which concludes with a phrase of near-Seinfeldian genius:

teresanh: You have to see this.
patricknh: waiting
(tnh sends URL)
patricknh: WHAAAAAAAT?
patricknh: This is a joke, right?
teresanh: It’s serious.
patricknh: This is stupid. I now have stupid all over me.