I have a pretty bad memory, which is why I write it down if I need to remember it. In TM4SA I remind people to write things down in practically every chapter.
Alternatively I have tried to improve my memory. Having improved memory helps all aspects of life. It turns out that memory is like a muscle: exercise it and it gets stronger, don't use it and it gets weaker. The techniques I learned help me in many little ways.
I found Page-a-Minute Memory Book to have very practical advice for improving my memory. The first part explains why we don't remember things so that we are more self-aware of how to fix it. That alone made it worth the price of the book. The second part has a lot of useful techniques for common things: how to remember people's names, remembering short lists, etc. I stopped reading when he started onto tips for remembering things that, well, would put you into the guinness book of world records. However, the remainder of the book was very helpful.
Last night I watched the 1957 Katherine Hepburn film, "Desk Set" (Amazon or Netflix). In this movie she plays the head of research for a major TV network. She has their entire research library practically memorized. When Spensor Tracy arrives to replace her department with a computer (very proto-Google, if I dare say) the hilarity ensues. (The movie is kind of shocking for the way it portrays office life in the 1950s. She's dating her own boss and there's no HR policy to stop it! The depiction of the computer is awesome.)
There's a great scene where Hepburn demonstrates the use of mnemonics as a way of improving ones ability to memorize random facts. She doesn't use the term mnemonics, but she shows show she's related anything she needs to remember to another fact. Since I use mnemonics (thanks to the Page-A-Minute Memory Book), it was great to see it in action and very interesting to see how the script portrays it.