Simple GMail Notes is the solution I've been looking for forever. Most of my life is somehow in GMail (sadly). For years, when I've wanted to make sure I recalled why I had or had not taken an action in response to an email, I forwarded the email to myself with my notes. Simple Notes is a far better tool for this purpose. I can drop a note on an email of anything I want to remember about that email and not only is it there when I go back to it, but there is also what is essentially a yellow flag next to the email (actually part of the note) that differentiates these emails from others.

As probably implied, I am not an empty-mailbox kind of user. I also have a busy life and a forgetful nature. I probably retain too much, but I have thousands of emails in my inbox and use search to find and recall communications I want or need to revisit. Having the note remind me of something not explicitly in the message is a life-saver. (Maybe that's a little dramatic, but it feels that way at times.)

My Palm handheld in the early 2000s had this functionality and I've been looking for it every since. The add-on works flawlessly and I like having it saved on my computer rather than in a third-party's server.

Now I need the same thing for my telephone calls.