I have been sitting here letting my mind wander while doing my work. Lots of things have crossed my mind, yet nothing has really stuck in there.

It's a shame that this happens. You want to grasp an idea and work with it, but as you are reaching for it, it fades and vanishes as another thought takes its place. I use to have such a good memory and thinking cap for things, but with age, eh...what was I thinking?