How to write an e-mail message
From ShawnReevesWiki
Subject line
Don't write vague subjects
Recipients use subject lines to organize the opening of e-mails, to know whether and when they should read the contents. If there is no distinguishing, specific subject, then the content isn't interpreted as useful or enticing. Following are some examples of useless subject lines.
Explanatory but not specific
"posting from friend.."