Rated 5 out of 5 stars
I found this so useful. Many people "reply" to me without a relevant subject line. So I have no idea whats in it or which e-mail it is. This lets you "label" the e-mails you receive in the edited subject line. That is a huge productivity boon. For example, if you get receipt from Amazon, the subject line is a long cryptic number. You can replace the subject line with "printer paper" and you know exactly what it is.