I don’t know where I learned this (it’s likely apocryphal), but Salvador Dali purportedly developed a special method to capture his unconscious ideas. When drowsy, he’d sit over a plate holding a spoon; as soon as he started to fall asleep, his hand would relax, the spoon would hit the plate, and the sound would rouse him enough to record what had passed through his mind as he was losing control over it. After he jotted down everything he could remember, he’d pick up the spoon and begin the procedure again.
I keep meaning to test this experiment, but I never think to grab a spoon when I’m tired. Still, I love the final thoughts that materialize before sleep, which are slightly more concrete than dreams (and thus more receptive to conscious manipulation) but share dreams’ liberating illogic. It’s possible that none of these thoughts are especially coherent; my vague memories of them have more to do with their flow than their content. And sharing enough bedrooms over the years has taught me that what a person considers astute when he’s falling asleep might strike him as gibberish when he’s fully awake—statements like “No, you’re my lion,” to quote my first college roommate.