Yes i use one.Just old fashioned one with the small tape(i guess i should call it ancient actually:).
I keep it by my bed to save myself troubles getting up at night ,turning the lights on,looking for a pen,writing.I record what i can remember and go back to sleep.On the morning or later during the day i usually write them down from there into (now thats ancient) notebook(with paper sheets).
take care.
If you don’t have an mp3 player, maybe you could buy one that has a voice recorder function. They are relatively cheap now, compared to a couple years ago.