Need a memory extension

Don't you have that all the time? Laying in bed, half awake, half asleep, thinking about the things that keep you busy during the day. All of a sudden, you have a smart idea, an idea you did not think of before. Still having your eyes closed because it's still too early to get up, you try to memorize this idea. Then, you fall asleep again and when you wake up the only thing that you remember is that you had a smart idea... But you lost it.

Only once in my life, I had the courage to get up and write it down. It turned out to be a smart, but impractical idea.

But the worst thing is that these kind of things not only happen during the night, but also during the day. No, I am not sleeping during meetings but I do get all kind of smart ideas during meetings, conversations, driving my car, dinners or having a walk with my dog. And every time I am unable to remember them afterwards.

Wouldn't is be a good idea to have a memory extension that would record these thoughts?