My memory's not so good so I deal with this by making lots of lists. My to-do- list for this week has a line that simply says "f". I have no idea what this was. It's most likely that it was such a short-time task I was certain by the time I looked at the list next the lone letter "f" would jog my memory into whatever it was I was trying to remember but, I guess it's also possible I just literally accidentally typed an "f" when I thought some other window had focus and it means nothing at all