I was going to say naked until I reread the question.
I used to sleep in a twisted position due to an accident when I was a kid. I would lay on my back and my lower half would be twisted so my knees were facing down.
I sleep on my side only in the fetal position if I'm really cold. I don't sprawl out since I have a cat and might kick her off. Sometimes I sleep in the coffin position (on my back with my hands folded on my chest).
Yearner almost exclusively, albeit with a pillow between my arms. (As someone else said, "hugging a pillow".) Sometimes I have a pillow between my legs, or I'll just shift one leg forward. I can't stand the feeling of knees touching, or the angle required of the shoulders with nothing between your arms.
I fall asleep with my legs curled up and I'm holding onto my pillow or have my arms beside me. When I wake up, I'm a either a bit more straightened out but still have my legs curled, or I'm laying on my back or side with my covers all weirder up, a pillow kicked onto the floor, and just super comfortable.
So you decide which one I am. I'd say most describe me at some point besides the Log position. That sounds too rigid to be comfortable.