Please, please, please, include a subject
line. No subject line does not make the message seem mysterious and compelling - really. Just makes you look lazy.
This goes along with "follow standard writing guidelines": please watch your punctuation! Somehow the ellipsis has become the most common punctuation in office email, at least where i work. It kills me. That, the typing in all caps, and the awful spelling and grammar can almost be kinda cute, in a pathetic, doesn't-know-any-better way - but these are adults!
Email is a form of communication and self-presentation.