I'm normally not a big re-poster of blog articles, etc but one I read today was pretty good. It's by Daniel Waldschmidt, sales guru and partner at Gnoso. He talks (rants?) about e-mail and how too many times we focus on ourselves and not the customer.
Go check it out - Your email just punched me in the eye
I know for one am guilty of this from time to time. Crafting good e-mails is a skill that's not learned overnight that's for sure!