Sleep and irretrievable ideas

I really need to start sleeping with a note pad or something beside my head. Often, I'll lie in bed for half an hour or longer, thinking or theorizing about something that I had been reading or working on and a really good idea will come to me. Unfortunately, unless I get out of bed to write it down, I usually can't remember it in the morning. (It's the same way with my dreams - about 10 seconds after I wake up, all I can remember is that I had a dream.)

Case in point: I distinctly remember thinking last night that I had an idea that I should blog about. But all I can remember now is that I had an idea. Of course, the caveat here is that if I can't remember the specific idea then I can't very well be sure that it was actually any good. Or that any of them are ever very good. (Almost-relevant Beatles anecdote: Paul McCartney often talks of a party where, in a drugged out haze, he told Neil Aspinall that he had discovered the meaning of life any Neil had to record it for him. When Paul woke in the morning he couldn't remember the meaning but recalled where he had put the paper. And written on the paper? "There are seven levels.")