[martin]

I've hired a couple of people recently, and personally I use cover letters to see how people write.

Not every hiring manager cares about this, but I will not hire somebody who can't write half a page of text without making egregious spelling, grammar and punctuation errors. I've seen cover letters that, when opened in Word, become a sea of red and green squiggles. It demonstrates a total lack of attention to detail, among other unflattering characteristics.

Sadly, I rule out a LOT of applicants this way.

[Retric]

Cover letters are often used to weed people out, so it's not always a good idea to create one. IMO, if you have a great cover letter include it, but if average or below skip it.