Let's face it...lots of the emails we receive have misleading or useless subject lines. This annoys me because my work day is full of emails and often I need to store them and be able to retrieve them later, and that's not easy to do when the subject is bad.
Even if a search turns up the right mail, if there's more than a few search hits, you need a reasonable subject line to find the right one.
That means that every now and then I get an email that I need to file and I would love to amend the title, but I'm not aware of any mail system that allows that.
I'm using gmail. I wanted to put this out there on the lazyweb and see if anyone has tried a feature like this.